Piranhas & Pacus
Piranhas are fierce little fish that swarm around animals unlucky enought to fall into the river, then tear
them to bits...right? Actually, some piranhas eat fruits, nuts, and seeds. Piranhas are more diverse than
you might think.
cast of mega-piranha jaw
These three fish are all related to one another. The mega-piranha is extinct now, but it has a lot in
common with present-day relatives like the pacu and the red-bellied piranha. They belong to an order of
fish called Characiformes, or characins, and within that order, are part of a subfamily called
Serrasalminae. Dozens of species are part of this group, and their body shapes and diets vary. You might
be familiar with some Serrasalminae such as the infamous red-bellied piranha, the large herbivorous
pacu, or the beautiful silver dollar.
Piranhas are an ancient lineage with fossils as old as 13 million years. In Argentina, Dr. Alberto Cione
discovered a fossilized jaw of a “mega-piranha”, a species fish that lived 6-9 million years ago. The
mega-piranha was a big fish, probably 1 meter (3 feet) in length. No one is sure what it ate, but it may
have been a plant eater like its living relative, the pacu. Although it is now extinct, its skeleton helps us
understand more about its present-day relatives. Judging from its teeth, it may fit in between the pacu
and the meat-eating piranhas on the evolutionary chain. Pacus have two rows of flat teeth; piranhas have
one row of razor-sharp teeth. The mega-piranha has a zig-zag row of teeth, suggesting that the two rows
of teeth in the pacus became compressed into one row in the evolution of piranhas. If this is so, the
mega-piranha shows us what fish looked like at the mid-point of that long, slow process.
Red-bellied piranha, Pygocentrus nattereri
This species is one of the few piranhas that deserve their fierce reputation. These schooling predators
usually target fishes, especially dead or dying ones, but sometimes also attack birds, small mammals, and
other critters that fall into the water. If you look at the piranha’s jaw, you can see the serrated row of sharp
teeth it uses to slice out bite-size pieces from its prey. Under normal conditions, they are not dangerous to
humans. However, the ebb and flow of the Amazon River creates floodplain lakes away from the main
channel that dry up at the end of the dry season. Starving piranhas trapped in these shrinking lakes without
food and with little oxygen can become extremely frenzied and attack anyone that comes in the water.
Pacu (or tambaqui), Colossoma macropomum
This fish looks quite a bit like a piranha, and but much bigger! The pacu may grow to three feet in length
and weigh more than 60 lbs! But don’t worry… they are herbivores, relying on a diet of fruits and nuts
that fall from the flooded trees. They may spend the entire dry season without food, but when the
floodwaters invade the forest, they do most of their eating and growing during the months of the wet
season, when trees are producing lots of fruit. If you look at their double row of flat teeth, you can see
how that may help them crush hard-shelled nuts – much like our own molars. Due to their size and
sweet-tasting meat, pacu are an important food fish for people who live in the Amazon basin – imagine
how tasty they are!
“Mega-piranha”, not named yet
Fossils are rare in the Amazon, and in the rest of the tropics in general. A warm, wet climate is about the
worst you can have if you want to find fossils. This rare fossil jaw turned up in Argentina a couple of years
ago, it belonged to a fish that lived 6 to 9 million years ago. If you look closely at the teeth, they form a
zig-zag shape. This may indicate that mega-piranhas are between pacus and piranhas in the evolutionary
chain. If this is so, the zig-zag shape shows the middle point in the process where the double row of
teeth rearranged themselves to form a single row.
The largest extant piranha is the black piranha Serrasalmus rhombeus, which is just over one foot long. A
large pacu may grow to three feet. So why is the mega-piranha so big? Why do animals go extinct? How
are herbivores and carnivores morphologically different?
Where Are All the Fossils?
Visitor makes fossil rubbing, spurs discussion of how fossilization occurs and why there are few fossils of
Option: may replace fish fossil rubbing with Plaster of Paris casting
Fossils are few and far between in the tropics. The conditions that allow fossilization to happen don’t
generally occur in those parts of the world. The short explanation is: in the tropics, things rot. The longer
explanation is: for fossilization to occur, an animal must die and remain undisturbed by scavengers. It must
also be protected from decomposition by various environmental factors. Its body may lie in oxygen-poor
water that does not support decomposing microbes, or it may lie in the hot, parching sun. The body gets
covered over by layers of sand, silt, or mud, which are compressed over time to form sedimentary rock.
Mineral crystals slowly slip into the body of the animal replacing the hard organic material (i.e. bones),
turning its skeleton to stone. If all of these factors come together, a dead animal becomes a fossil.
Those factors don’t often come together in the tropical regions. Because of the hot, humid climate,
fossilization rarely occurs. That means that scientists who study the paleo-history of tropical regions can’t
get as much information from the fossil record as scientists who work in temperate regions of the world.
Fossils are helpful to scientists because they help them understand the evolutionary path that a present-
day animal has followed through time. Fossils may be able to tell you how long a given animal has
existed, which animals were its close ancestors, and how its physical features have changed to suit its
environment. Fortunately, fossils that are found in other areas of the world may sometimes provide
information that scientists who work in the tropics apply to their own research.
About this fish fossil
This fish is a type of herring called Knightia alta, and it lived 50 million years ago in the Eocene era. The
fossil was found in Montana in a fossil-rich site called Green River. Although this particular species is not
tropical, it does have relatives in the Amazon region. Knightia alta is a member of the family Clupeidae, or
anchovies and herrings. These silvery schooling fish are mainly ocean dwellers, but a type of herring
called Ilisha amazonica lives in the Amazon River today. Many fish that are mainly oceanic, like stingrays,
pufferfish, and flounder, have freshwater relatives living in the Amazon River. These date from a time
when the Pacific Ocean and the Amazon River were connected, over 80 million years ago. Oceanic animals
entered the Amazon until the rise of the Andes mountains cut the river off from the sea, trapping marine
animals in the river basin. Many species died off, but of the few survivals, and descendants of those
survivors swim through the Amazon today.
This activity lends itself well to further conversations about the geologic history of the Amazon basin (i.e.
tectonic movement, mountain formation, massive droughts and floods, etc) as well as an inquiry-based
discussion regarding the differences between fresh- and salt-water animals.
Remember: life began in the ocean!
Meet an Animal
Get to know some of the small animals of the Amazon by holding them in your hands. Demonstrator carries
animal replicas and explains some of their special adaptations and interactions with other species.
jar of Styrofoam balls to represent snail eggs
“Muckfish”, not named yet
This fish lives in the woods! Some fish in the Amazon basin are practically terrestrial, at least during
some parts of the year. During the wet season, the forest floor is flooded, and the leaf litter that thickly
coats the ground is inundated with water. During the dry season, water recedes, leaving muddy piles of
leaves at the edges of lakes and streams. Almost 50 species of fish can be found buried in these leaf
piles, entirely away from the river. So why is this muckfish so cool?
1. It lives in wet piles of rotting leaves; not open water.
2. It can breathe both air and water.
3. It’s the only freshwater fish with backwards scales on its head.
4. Its swim bladder has ten air chambers; most fish have two.
5. It has no visible lateral line to sense water movement; almost all other fish have it.
6. It is only found in this one place in the whole world.
7. It has been there for 50 million years, yet scientists just discovered it.
8. It could be the great grandpa of all catfish and piranhas.
9. It’s not only a new species; it’s also a new genus, a new family, and maybe even a
new suborder of fish.
10. It’s so ugly, it just has to be cool!
Pipa toad (or Surinam toad), Pipa pipa
This is possibly the weirdest-looking animal in the Amazon basin. It’s a highly aquatic amphibian that
floats in murky waters camouflaged to look like dead leaf. It surfaces to breathe about every half hour,
but it probably also absorbs some oxygen from water through its skin. It uses unique senses to navigate
without seeing: tentacles on its fingertips offer tactile information, and pressure-sensitive organs on its
sides detect vibrations in water (these vibration-sensitive organs denote solid objects like rocks and tree
trunks or moving objects like other animals). The pipa toad opens its mouth and expands its body to suck
in water, hence vacuuming up all moving prey; and oh yeah! It eats just about anything that fits in its
mouth (captive juveniles can eat their own weight in one feeding). When it comes to dead food and slow-
moving prey, this toad stuffs it into its mouth with its front feet, how charming! It reproduces in the
strangest way imaginable: male and female do loop-the-loops in the water as they mate, managing to
place and fertilize the eggs on the female’s back. Her skin grows up around the eggs, enclosing them in
cysts (the scientific word for ‘lumps’) with clear tops, though which the developing froglets are visible.
They grow there and develop through the tadpole stage, emerging as froglets with tails.
Apple snail, Pomacea sp.
Apple snails are found all over the world. This Pomacea lives in freshwater habitats like ponds, streams,
marshes. It is well-equipped for seasonal fluctuations in water levels, as it has a gill, a lung, and a
snorkel! When it swims, it gets oxygen from the water with its gill. In low-oxygen water, it can take air in
from the surface with a snorkel-like tube called a siphon. Its lung processes air from the siphon. It can
also breathe on land if it must travel from one body of water to another. If water dries out altogether,
Pomacea snails can bury themselves in the mud, seal their shells with a trap-door called an operculum,
and wait out the dry season in a suspended state called aestivation. In water, apple snails can detect
predators by smell – their eyes can only tell dark from light. They can also tell when other snails are in
trouble – juice from crushed snails in the water causes them to close their operculum, drop to the bottom
and bury themselves in sediment. Wow! It eats mostly vegetation, scraped into bits with a rasp-like
tongue called a radula. It also eats dead fish, frogs, insects, and crustaceans; and it is eaten by fish,
turtles, rats, and birds like grackles, limpkins, snail kites. The snail kites are named so because they can
eat snails, their curved beak is specially adapted to insert into shell, cut muscle-holding animal inside,
and pry out the snail’s soft body. Snail kites are common in the Amazon, but they are endangered in
Florida. It reproduces by laying eggs on rocks, branches, and living plants just above the water line. The
eggs must stay dry, if water level rises at the wrong time, the eggs will drown and the tiny snails inside
them die. In Florida, flooding water levels are in the control of humans, who often flood the Everglades at
the wrong time of year – the effects of this are far-reaching, including killing snail eggs and thus
depriving Florida snail kite of its only prey.
Very brightly colored clumps of 100 to 1000 eggs - white, cream, pink, green, or orange – are sprinkled
throughout the Everglades, the Amazon’s flooded forest, and many other apple snail habitats. Although
the snail’s eggs are very conspicuous, predators do not eat them – possibly because they taste really
bad. Human researchers have tasted them and found them to be nauseatingly bitter.
What Is It?
Through written descriptions and object ID, visitors look closely at Fabric of Life drawing to appreciate the
diversity of the Amazon’s plants and animals. Primary activity: visitors identify objects and match them
to corresponding animals in the Fabric of Life drawing. Secondary activity: visitors read/hear descriptions
of selected animals and match them to corresponding animals in the Fabric of Life drawing.
specimens (i.e. turtle shell, fish jaw, dry scales, etc)
list of animal descriptions
Ray Troll’s Fabric of Life drawing
demonstrator’s key (that is, a copy of the drawing with selected animals highlighted)
In the Fabric of Life drawing, the artist Ray Troll (artistic director of the Amazon Voyage: Vicious Fishes &
Other Riches exhibition) captures the legendary diversity of the plants and animals that live in the
Amazon. Here are some interesting facts about bio-diversity in the Amazon:
1. It would take you a long long long time to count up all the species of plants and animals
found there. Scientists estimate that there are more than 2,000 species of fish, 1,500
species of birds, 1,800 species of butterflies, and 50,000 types of higher plants.
2. A single lake in the Brazilian Amazon may have more types of fish than all of Great
Britain’s lakes and rivers.
3. Scientists believe that there are more types of fish in the Amazon basin than in the
entire Atlantic Ocean.
4. A single tree in Peru was found to have 43 species of ants living on it.
5. 3,000 types of edible fruits grow in the Amazon; North Americans eat about 200.
6. More than half of the world’s species of plants and animals live in the Amazon basin
and Andes mountains.
Primary activity: handle an object (Note: edit text according to specimen)
What is it?
The smooth, round, flattish shape tells you this is a freshwater turtle. Specifically, it’s a sideneck
turtle, one of many freshwater turtles living in the Amazon River. It gets its name from a sideways
s-bend in its neck that allows it to pull its head deep into its shell. Although cartoons often depict
turtles taking off their shells and wandering around without them, a turtle’s shell is part of its body,
growing as the turtle grows and firmly attached to its skeleton. Most predators are foiled by the
bony shell, but caimans and pink dolphins can crunch right through it.
Secondary activity: Hear a description
Where is it?
Silky anteater, Cyclopes didactylus
This little creature is related to armadillos and sloths. It spends its days sleeping and its nights
looking for tree-ants. It breaks open ant nests and licks out the ants with its long, saliva-coated
tongue. Its curved claws and long prehensile tail help it climb through the treetops, and its thick,
short fur protects if from ants’ defensive bites.
Harpy eagle, Harpia harpyja
This giant eagle is one of the largest in the world; it can weigh as much as two bald eagles. Its
talons are the size of a human hand, enabling it to prey on large animals like monkeys and sloths.
Matamata turtle, Chelus fimbriatus
Unlucky fish discover that these odd-looking turtles are impossible to see in a pile of leaves. Their
tube-shaped nostrils and long necks allow them to reach the surface and breathe air while lying
perfectly still, waiting for prey to pass by.
Pink river dolphin (aka boto), Inia geoffrensis
Bubble-gum pink, very small eyes, a huge melon and a long snout, the boto relies on its sonar to
navigate murky waters and find prey. Instead of a dorsal fin, it has a hump on its back – probably to
help it navigate through the branches of the flooded forest.
This relative of the grasshoppers and crickets is colored to look exactly like a leaf, right down to
details like holes, nibbled spots, and splatters of bird poop.
Howler Monkey, Alouatta sp.
The loudest land animal on earth! When the howler calls, a pouch of skin on the neck inflates to make
a natural amplifier. Their rolling, burping cry is audible for three miles or more, and is used to defend
territory from other howlers. Drink a whole lot of soda and you’ll be sounding like a howler too!
Fish Need Trees Too
The tray filled halfway with water represents a plot of land sloping down towards a river. The sponges on
the shallow end represent forested land. The demonstrator uses a beaker full of water and glitter to
represent pollution (i.e. farm runoff, sewage, trash, or chemicals from mining and other sources). She
pours half of the contents of the beaker over the top of the sponges to see how much “pollution” runs off
into the river. Water should run almost clear. Then she removes large patches of sponges and pours the
remaining liquid mix over the same place where the sponges were. The river end of the tray should wind
up full of glitter, reflecting the pollutants that run off of bare land.
sloped paint roller tray
Deforestation affects water quality. When rainwater runs down sloping land into a river, it may carry many
things with it. If water runs over paved roads, it will pick up motor oil and gasoline. If the water runs through
a farm, it will carry fertilizers and pesticides from the fields. Trash and sewage from towns and settlements
can wash into the river as well. Vegetation along the edges of a river helps keeps the water clean. Plant roots
and soil trap garbage and neutralize chemicals before they make it downhill into the river. Tree roots also
hold soil together, and prevent erosion so that mud and sediments are not washed away.
Silt and dirt run off degrades water quality and affects the animals in it. It can upset the food chain,
smother fish, blur their sight, and even disturb animal reproduction. As for plants, suspended sediments
in the water block sunlight, affecting their growth; aquatic plants provide food for herbivorous fish and
anchoring spots for other fish to lay their eggs. Runoff also affects the lives of humans. Millions of people
who live along the Amazon River, depend heavily on clean waters for their survival. They use the river for
fishing, hunting, transporting people and goods from place to place, drinking, playing, etc.
Discuss issues regarding logging in the Amazon. Hardwood trees provide wood for furniture, building
materials, and charcoal. Although there have been some efforts to protect noble woods, the trade of
tropical trees is still common. Increased funding for government protection of rainforest areas, may one
day help protect these ecosystems.
Life along the river presents many challenges to local people. Yet they meet these challenges in creative
ways. Visitors build a floating cow pen, float it on a tub of water, then they load it up with as many toy
cows as possible before it sinks.
container of water
toy cows, chickens, goats, or pigs
Millions of river people live along the banks of the Amazon River. You may imagine them as being tribal
people, but the majority of them are descendants of European colonialists, African slaves, and
Amerindians. Only about 1%, or 230,000 of the 23 million people in the Amazon are Native Indians.
Although many Amazonians live in large cities like Manaus, Belem, and Iquitos, the river people conduct
most of their personal and business activities right on the river.
How would you build a house along a river that rises and falls as much as 30 feet each year? Do you think
that the floods are disastrous? On the contrary, river people do not try to dam the river, wall it in, or
contain it; the yearly floods bring riches that the plants and animals depend on to survive. The riches
include fish for eating and nutrients deposited on their agricultural lands. So, to accommodate these
drastic but welcome changes in the water level, people build houses that float! Building a house on a
wooden platform and attaching it to a piling is an ideal way to cope with the rise and fall of the river.
People’s homes are not the only thing float either, stores, hospitals, churches, and even pens to hold
farm animals are on the water.
Aside from the small numbers of livestock mentioned above,
much of the food people eat comes from the river. Fish and
other aquatic animals provide people with protein, which is
rounded out with grains and vegetables from small
subsistence farms. The river’s surrounding forests provide
additional materials used in daily life, like firewood and
medicine. Branches, logs, and salvaged planks are used to
build floating houses and other structures. Large trees can be
hollowed out to make dugout canoes, and slender saplings
can be used to make fish traps. Palm fronds can be used to
thatch roofs or weave baskets. What would you build if you Floating Chicken Coop
lived on the Amazon? Photo by Sean Duran
Add a discussion on sink-and-float.
Add a discussion on botany (i.e. how come the trees don’t rot when they’re flooded).
Does Rubber Come from Trees?
The rubber tree, Hevea brasiliensis, is a tropical tree, native to the Amazon basin. Start by asking visitors
if they can think of items they use daily that are made of rubber (for example: soles of shoes, tires, latex
products such as gloves, erasers, and gaskets).
Making an elastic material
The material we will make is not actually “rubber”, but is similar in structure (an elastic polymer) and in
texture (flexible and bouncy). White glue (a chemical polymer), water, and borax soap powder are used to
model the making of a rubbery product. Also needed: plastic drinking cup, of food coloring, paper towel,
and rubber gloves.
1. Measure 25 ml of Elmer's glue into a plastic drinking cup.
2. Add 20 ml of tap water to the glue. (In the event that you have nothing with which to measure liquids,
this is roughly a 50/50 mixture of glue and water.) Five drops of food coloring can be added if
desired. Stir very well until the ingredients are completely mixed.
3. Add 5 ml of borax. Stir well.
4. A solid material will begin to collect on the stirrer. Remove the solid material and place it on a paper
towel. Knead the material with your fingers. The material will be sticky for about a minute or two. It
will become more puttylike as the substance loses excess water.
Note: Some people are sensitive to borax, so make sure you wear rubber gloves.
1. Does the material stretch? Does it go back to its original shape afterwards?
2. Roll some of the “rubber” into a ball, will it bounce? Why?
According to some scientists, the latex is a defense against wounding and/or predators such as insects
During the early 1900’s, rubber was harvested from "wild trees" scattered throughout the rain forest.
Rubber is gathered by tapping—making a small incision in the bark of a rubber tree and collecting the
milky white sap that oozes out into a bucket.
A rubber tapper goes back to the same tree again and again to tap its sap.
To cure the rubber, the tapper builds a fire of green palm nuts and smokes the latex over it. As the tapper
twirls his paddle over the fire, the latex thickens into rubber. After a while, a 70 to 80 pound ball of
rubber is formed.
Rubber is a polymer
• A polymer is a long molecule.
• This long molecule consists of structural units and repeating units strung together through chemical
bonds (like a chain).
• The process of converting these units to a polymer is called polymerization.
The units that make up polymers are called monomers. Monomers are typically small molecules of low
• What else is a polymer? (i.e. hair and cotton)
• Rubber polymer units have cross-links that allow it to be pulled in different directions and return to its
• Depending on the chemicals added to rubber, products made of rubber can be as soft as a sponge, as
resilient as a rubber band, or as hard as a bowling ball. As a result, we use thousands of rubber
products with varying degrees of hardness in our daily lives.
Some facts about rubber production
• Natural rubber has been available for centuries, synthetic rubber for less than a hundred years.
• Rubber production in the Amazon today is almost non-existant. In 1876 rubber seeds were taken from
Brazil by Henry Wickham to Kew Gardens in England (smuggled or legally exported, depending on one's
point of view). Seeds from rubber trees were then exported to Asia, where labor is cheaper and the trees
don't have the same natural threats. This is key to the economic boom and crash of the region.
• Not until after World War II was the quality of synthetic rubber to the point that it rivaled that of
• In 1960 the use of synthetic rubber surpassed that of natural for the first time. Synthetic rubber has
maintained the lead ever since. About 30% of the rubber used today is natural rubber. Airplane tires
are made from 100% natural rubber and automobile tires are 35-40% natural rubber.
Discuss biopiracy - the theft of biological resources. The people of developing countries are strongly
criticizing the companies of developed countries for their enclosure of genetic resources. They claim that
pharmaceutical companies, nurseries, and universities are developing medicines and other goods from
native species of their home countries without giving them proper compensation They also claim that
they have been protecting and utilizing these plants from long before they were discovered by these
companies, and that the acquisition of patents prevents them from freely using these plants and seeds.
Leaf It to Me
Primary activity: Demonstrate the immense size of some rainforest leaves; the importance of these
species; and why in the world they are so big. Secondary activity: talk about one of the basic
characteristics of ALL plants—the presence of chlorophyll and the ability to produce chemical energy from
Four (prepared) life-sized felt leaves to be laid out on the floor. Visitors can compare the Amazon leaf
size to the size of most North American leaves, and to their own body size (some leaves are bigger
than a grown person).
paperclip or a penny
Introduction to Amazon plants
• 90% of photosynthesis takes place in the canopy (the top layer of leaves that is found high above the
forest floor, ap. 100 feet)
• Most of the sunlight is absorbed by the canopy leaves, the forest floor is dark under the cover of the
• Rain and wind cause high branches to break and leaves to fall to the forest floor, where they are
QUICKLY broken down, nutrients are returned to the soil, and allow trees and other plants to grow
• Decomposition occurs rapidly in the tropics because of the warm, moist conditions, which allows
decomposers (bacteria, fungi, insects) to thrive
Primary activity: examples of rainforest leaves
Philodendron (ap. 3 feet or 0.914 meters wide)
• Popular houseplant, easy to grow
• One of the most effective houseplants for removing pollutants from the air. It filters formaldehyde
in the home (e.g. carpets, particle boards, and silk flowers).
• Philodendrons produce aerial roots that grow from the limbs and trunk to the ground, providing
additional support in the shallow soils of the rainforest, as well as drawing water and nutrients
• The name derives from the Greek: philo=love and dendron=tree (because they often use other
trees for support to grow towards the light)
• Over 500 different species
• Should not be eaten! It’s toxic.
Banana (ap. 6 feet or 1.828 meters long)
• Bananas are the most popular fruit in the world
• Comes from the Arabic word for finger (because of the shape of the fruit)
• According to the MABB, there are 35 species of bananas and 1000 cultivars, sub-divided into 50
groups (International network for the improvement of banana and plantain). The ones we eat are
usually the sweet Cavendish bananas (some types of bananas must be cooked to be edible)
• Fibers from the plant are strong—used in tea bags, paper money
• Leaves can be used for roofing, umbrellas, cooking, and to make mats
• Nutritious- lots of potassium, needed for brain functioning
Giant Waterlily (ap. 5 feet or 1.524 meters wide)
• Two species Victoria amazonica and Victoria cruziana are known
• It has 12” flowers (the size of a football) that open at night and are pure white, a chemical
reaction heats flowers to as much as 20°F above outside temperature and releases a sweet
pineapple smell to attract scarab beetles covered in pollen from other flowers. The bloom closes
and traps the beetle inside who pollinate this flower, collect more pollen, and then are released at
dusk the next day. Once pollinated, the petals change from white to purple, no longer attracting
other scarab beetles. The seed takes a year to sprout after pollination.
• The bottom of the waterlily is covered in 1 inch spikes to protect it from herbivorous fish
• The ribs on the bottom of the leaf are filled with air that keeps the lilypad afloat
Breadfruit, Artocarpus altilis (ap. 3 feet or 0.914 meters long)
• Native to South East Asia, brought to the Amazon by Europeans
• Pollinated by Old World fruit bats
• Grapefruit-sized, edible fruit, related to figs
• Flesh, when roasted said to taste like fresh baked bread
• The trees provide construction materials, medicine, fabric, glue, mosquito repellent, animal feed,
• Provide shelter and food for Amazon animals
• Can produce 800+ fruits a season, although this is variable and dependant on the location,
Why are these leaves so big?
1. To catch sunlight beneath the canopy - much of the forest floor is shadowed by the taller forest
canopy, many plants have large leaves to create more surface area for light absorption.
2. Because the growing season is YEAR ROUND (rainforest are near the equator so there is ample
sunlight and warmth all the time, plants never have to deal with winter)
3. There’s constant 12 hours night/day
4. There’s plenty of rainfall, so water is not a limiting resource
Secondary activity: Chlorophyll & Photosynthesis
• Chlorophyll allows plants to convert sunlight into chemical energy (food) through a process called
• Water (roots) + Carbon Dioxide (air) + Light (sun) = Sugar + Oxygen
• The sugars allow plants to make more cells and grow
• Oxygen is released into the air for organisms to breathe, the Amazon supplies 20% of the world’s
• One of the main differences between plants and animals is that plants are able to make their own
food (autotrophs) and animals eat other organisms for food (heterotrophs)
• Chlorophyll is the pigment in leaves that give them their color, but green isn’t the only color there!
Plants often stop producing chlorophyll in the fall (because they aren’t growing then), which is why up
north leaves change colors.
Anthocyanins—Red (they make apple skin look red)
Different types of leaves have different color pigments
1. Draw a line with pencil on a strip of coffee filter about ? inch from the bottom
2. Place a leaf over the line and roll the edge of a penny (or any other narrow object, like the edge of
a paperclip) over the leaf to impress some of the pigments on the filter.
3. Tape the top of the filter to a pencil or popsicle stick
4. Put ? inch of 91% isopropanol alcohol in a cup and place the end of the filter in it (making sure
that the green pigment is not touching the alcohol)
5.Set the cup aside and as the isopropanol moves up the coffee filter it will carry the pigments with
it. The different color pigments will be separated out into different colors because some are larger
and therefore heavier, than others.
Plants use pigments in their leaves to capture light from the sun, which they need to make food. The
most important pigment for this is chlorophyll a, which is what makes plants look green. Leaves also
contain “helper” pigments such as chlorophyll b (green), xanthophylls (yellow), and carotenoids
(orange). Different colors of leaves will show different pigment patterns—have visitors compare the
patterns of different leaves (e.g. spinach, kale, lettuce, leaves from outside etc.)
Other things to discuss:
• Plants in the Amazon produce 20% of Earth’s oxygen
• Plants provide food and shelter for animals
• People depend on plants as a natural resource—for food, medicine, building material, fibers for
clothing, decoration etc.
Demonstrator has two bags of equal size filled with different types of leaves. Scatter North American bag
and let people sort them by shape to see how many species they can find; then do the same with the
Amazonian bag. How many types of leaves can they find in each bag? Diversity is much higher among
tropical Amazonian leaves.
Two bags of leaves: one is of cut-outs from Ray Troll’s Leaf Diversity drawing and one from a plant
images book (North American species only).
Preparation: photocopy the drawings/images onto green and brown paper, cut them out.
Note: leaf images may come from other sources, just make sure that they are region-specific.
What’s biodiversity? Bio means “life” and diversity means “variety”
1. the variety of genes within every organism
2. the variety of species, like the giant water lily, red-bellied piranha, human being…
3. the variety of ecosystems, like rainforests, coral reefs, wetlands…
Biodiversity also refers to how all of these genes, organisms and ecosystems are interconnected. Most
species depend on one another – directly or indirectly – for their survival. The loss of one species or
habitat may lead to the loss of others as well.
Biodiversity in the Amazon
• Biodiversity tends to be much greater in tropical regions than temperate regions such as North
America and Europe. The Amazon rainforest contains the greatest biodiversity on Earth.
• The region is home to ~2.5 million insect species, tens of thousands of plants, and some 2000 birds
• The Amazon rainforest has 50,000 species of woody plants like trees and shrubs. That’s not counting
ferns, orchids, grasses, palms, air plants, or small soft-stemmed plants.
• A patch of forest the size of two football fields can have more types of trees than all of Florida.
• 3,000 types of fruits grow in the Amazon. In North America we eat about 200 types of fruits.
• Peru, one of seven countries in the Amazon, has 17,000 types of flowering plants. That’s more than
all of Europe and almost as many as the U.S. and Canada combined, which have 21,000.
Why is there so much biodiversity in the Amazon?
The Amazon has hillsides, mountaintops, floodplains, swamps, lowland forests and elevated
forests, called terra firme. Trees give space for other plants to live on; air plants, climbing vines, and
hanging vines cover their branches and compete with one another for light. As all of these areas
have unique environmental conditions, plants have diversified into many unique species that can
take advantage of these conditions.
Over many millions of years, geological processes have changed the face of the Amazon. The Andes
mountains rose, and rivers and tributaries moved their positions, changed course, and separated
pieces of land from one another. Whenever living things are divided into separate populations, they
tend to change in different ways from their old neighbors. Eventually this process of change gives
rise to new species.
Life in the tropics is kind to plants. Near the equator, the temperature is stable all year round, the
days are nearly always the same length, it rains all the time, and the earth gets more energy from the
sun than anywhere else on Earth. When plants have a year-round growing season, plenty of water,
and do not have to contend with freezing winters or short days, many more types can survive.
A huge variety of environments, over space and time, leads to a huge variety of species, so the
speciation rate in the Amazon is high. Because of the equatorial climate, extinction rates have been
low over most of the Amazon’s history. Given a long period of time with many new species
appearing and few species disappearing, the total number of species will grow and grow.
Why is biodiversity important?
• The biodiversity of the Amazon rainforest helps maintain our global climate, and provides
essential foods and medicines
• It contains untapped economic opportunities
• It supports natural services (fresh air, clean water, productive soils)
• It provides medicines and natural products (humans only use about 150 species of plants for food,
out of a possible 80,000 potentially edible plants. Diverse species help maintain resistance to
disease and protect our food sources)
• It has an economic value (tourism, medicine, food, environmental services such as water filtration)
• It creates natural beauty that we all appreciate
• Discuss leaf shape (i.e. dripping tip, size, etc)
• Discuss types of plants (i.e. nonvascular plants vs. vascular plants, vascular non-seed bearing vs.
vascular seed bearing, and seed bearing non-flowering vs. seed bearing flowering)
• Discuss issues with biopiracy: While Brazil has some of the most advanced laws to avoid biopiracy (or
unauthorized use of natural resources), enforcing them is a problem.
• Different species share characteristics, having evolved to cope with the hot, steamy conditions: large,
shiny leaves with “gutters”, drip-tips designed to shed excess water, trees with stilts or buttress roots
for support in the thin soil, and leaves with purple underbellies that act as reflectors to bounce back the
2% of light that filters through to the forest floor, so getting a double dose.
Anacondas & Indigos
Aquatic animals can be much larger than terrestrial ones. Visitors guess the length of the largest snake in
North America (the indigo) and pull out a rope to find out the length of the animal. Then they do the same
thing with the largest Amazonian snake (the anaconda).
Box with two ropes coming out of two holes, representing the anaconda and indigo snakes. Snakes can
be pulled out, one at a time, and reeled back in.
The green anaconda is the largest snake in the world. Water to loll around in and plentiful large prey have
enabled the anaconda to grow large and laugh at predators. North American snakes don’t have the same
opportunities, and thus have remained small. The largest non-venomous snake in the U.S., the indigo, is
not anywhere near the anaconda’s size.
• Largest anaconda – close to 28 feet, 44 inch girth, estimated 500 lbs. Larger sizes are reported, but
these are from skins, which can stretch up to 30%. Also, the python can be a couple of feet longer,
but the anaconda is still much larger.
• Largest indigo snake – 103.5 in (8.5 feet) – more typical size is 60 to 75 inches. Under 15 lbs, exact
record weight not available. The eastern diamondback rattlesnake is also very large – seldom over
seven feet, but can be heavier than the indigo snake.
It’s important to compare the record size to the average size of the animal to get a true picture of the
species. For example, how big would you say a human is? A human is somewhere between 5 and 6 feet
and 150 to 250 lbs… but there have been people over 8 feet tall and over 500 lbs. So large anacondas in
the normal range are 15-17 feet and 150-200 lbs. Large indigos in the normal range are 7 feet long and
weigh about ten pounds.
How did the anaconda get so big?
1. Available resources create niches that animals evolve to fill. The anaconda probably evolved from a
tree dwelling boa. Going down to the river to explore an area with less competition and more room
2. Once in the water, the anaconda’s ancestors found great advantages: it’s much easier to move a
large body in the water because the water helps support its weight. Imagine how hard it would be to
drag yourself around on your belly if you weigh 200 lbs!
3. Water also conceals the anaconda’s large body: when it hunts, only its eyes and nostrils stick out of
the surface, and as an unsuspecting animal comes to the lake for a drink… SNAP!
4. Large prey is readily available in the Amazon, in graduating sizes too. That means that as a snake
grows in size, it can move from small prey to medium to large.
5. The anaconda has no true predators. Other than a few animals like caimans, jaguars and piranhas,
which eat anacondas when they are young—no one else is bold enough to take them on.
6. Large snakes can take larger prey and thus hunt less often, decreasing their chances of being hurt
Indigo snakes are large compared to their North American cousins, and they rely on their size and weight
to help them catch their prey. Indigos are capture feeders, holding their prey down with their heavy
bodies instead of constricting them like other non-venomous snakes. So why don’t they get bigger and
take on larger prey? (1) there aren’t as many large prey animals in Florida and Georgia as in the Amazon;
(2) the marshy, watery habitat that anacondas thrive in is not as extensive in North America; and (3) large
reptiles do not do well in cooler climates. All reptiles need their bodies to warm up to a certain
temperature range before they can be active enough to hunt. Smaller-bodied reptiles can take advantage
of a few warm hours on a sunny winter day, but larger reptiles take so long to warm up that they can’t get
going until spring rolls around.
Discuss size of other animals: The blue whale relies on water to hold up its mind-bogglingly huge body,
weighing up to 200 tons and stretching as long as 100 feet. Our largest land animal, the African elephant,
has to rely on its skeleton for support and maxes out at 7 tons. It’s said that a herd of 30 elephants could
fit in a blue whale’s tongue! Even the largest land animal that ever lived, the Brachiosaurus dinosaur,
weighed an estimated mere 50 tons.
Order the Fish
All bony fish belong to the Kingdom Animalia (Animals), the Phylum Chordata (Having a Backbone), and
the Class Osteichthyes (Bony Fish); but this is where it begins to get complicated. How is a pufferfish
different than a catfish? How is a piranha different than a flounder? This level of classification is called
the order. Visitors try their hand at classifying fish by sorting fish images into four different categories, or
orders. The demonstrator asks visitors to look carefully at the tails, fins, barbells and skin of the fish on
each card and see if they can identify what morphological characteristics they have in common (i.e. a
long and thin body with a fringe-like dorsal fin denotes a knife-fish).
Pictures of fish mounted on foam core.
There are about 15 million species of organisms on Earth! To make sense of them all, scientists identify
the features they have in common and classify them into established categories. Each category becomes
more specific and includes fewer organisms than the one before. The last category is made up of just on
kind of organism, namely a species.
Scientists aim to discover and describe all of the fish species in the world. Discovering all of them will
help us understand how they evolved and how they fit into the ecosystem. This information will also help
us identify and protect species threatened with extinction.
• Discuss animal classification: each category of the classification system is divided into smaller and
smaller groups all the way down to a single species. The primary categories are Kingdom, Plylum, Class,
Order, Family, Genus, and Species.
• Other orders of Amazonian fish include: Beloniformes (needle fishes), Order Cyprinodontiformes
(rivulines, killifishes and live bearers), Order Lepidosireniformes (South American and African
lungfishes), Order Osteoglossiformes (bony tongues), Order Pleuronectiformes (flatfishes), Order
Tetraodontiformes (puffers and filefishes)
Order Characiformes (characins: piranhas, pacus, tetras, headstanders, hatchetfishes, and their relatives)
Red-bellied piranha Wimple piranha
Pygocentrus nattereri Catoprion mento
Bleeding heart tetra Elongate piranha
Hyphessobrycon erythrostigma Serrasalmus elongatus
All photos by Mark Sabaj
Order Gymnotiformes (knifefish)
Longtail knifefish Banded knifefish
Sternopygus macrurus Gymnotus cataniapo
Barred knifefish Natterer’s channel knifefish
Steatogenys elegans Sternarchogiton nattereri
All photos by William Crampton
Order Perciformes (perch-likes)
Freshwater angelfish Oscar
Pterophyllum scalare Astronotus ocellatus
Photo by Mark Sabaj Photo by William Crampton
Button peacock bass Demon eartheater,
Cichla monoculus Satanoperca jurupari
Photo by Paulo Petry Photo by Garold Sneega
Order Siluriformes (catfish)
Sturgeon catfis Sailfin catfish
Platystomatichthys sturio Leiarius marmoratus
Polka-dot catfish Slender shovelnose catfish
Pimelodus pictus Sorubim elongatus
All photos by Mark Sabaj
Mouths and Tools
Visitor compares tools to mouth of fish to understand adaptations for different diets and feeding methods.
Visitor takes tool from basket and hangs it from hook under picture of corresponding fish.
Basket (or tool belt) full of tools.
Pegboard with pictures of fish at top, hooks beneath.
The thousands of fish in the Amazon River eat thousands of different things, and many fish have mouths
that are specially adapted to their diets. The demonstrator hands out images of fish and tells visitors
about their feeding habits. Visitors then try to match the fish images to the kitchen tools on display.
Salad tongs & Piraíba
These large predators have mouths shaped like
a duck’s beak, to firmly grasp their prey.
Photo by Mark Sabaj
Strainer & Highwaterman catfish
These fish strain plankton out of the water with stiff,
comb-like gill-rakers in their throats.
Photo by Mark Sabaj
Meat fork & Payara
This predator attacks from below, using two sharp lower teeth,
which it uses to pierce its prey. Holes in the top of its mouth give
the teeth a place to go when its mouth is closed.
Photo by Paulo Petry
Saw & Largetooth sawfish
Sawfish kill their prey by slashing at them with
their toothy snout (called a rostrum).
Photo by Éden do Carmo Soares
Nutcracker & Tambaqui
Tambaquis use their flat crushing teeth to eat seeds and
nuts that fall into the water from overhanging trees.
Photo by Ray Troll
Suction cup & Jaraqui
Jaraquis have a sucker-shaped mouth, which they use
to suck and scrape algae off of rocks and tree branches.
Photo by Mark Sabaj
Turkey baster & Tamandua tube- snout knifefish
Tube-snouts probe the soft river mud for food with
their elongated mouths.
Photo by William Crampton
Utility can opener & Wimple piranha
This piranha does not usually eat its prey whole – instead,
it uses its upper jaw to dig in and its lower jaw to scrape away
scales. Its victims generally survive and produce more scales
for more wimple piranhas to eat later.
Photo by Mark Sabaj
Tamandua tube - snout knifefish
How do you figure out how many animals there are in a given area? Mark-recapture sampling is one such
way. Visitors figure out how many grains of rice are in a jar with mark-recapture sampling.
1. Prepare a jar with a known number of rice grains. Write down that number but do not show it to
2. Scatter the rice in the cup on a tray, and pick up grains one by one for 10 seconds. Count the picked
up grains, record the number (first catch), and mark each grain with a dot.
3. Put the rice grains back into the cup and shake it up so marked grains mix thoroughly with unmarked
4. Pour all the rice grains back onto the tray. Pick up grains one-by-one again for 10 seconds. Count all
the picked up grains and record the number (second catch). Then count the marked grains in your
sample and record that number (marked found in second catch).
5. The ratio of marked to unmarked mirrors the ratio of caught “grains” to total “grains” in the “area”,
first catch X second catch
marked found in second catch
Example: if you get 26 grains in your first catch and 28 in the second, and 2 marked ones turned up
in your second catch, your equation is (26 x 28)/2, and your population is 364.
6. Reveal to the visitor the total number of grains in the jar and find out how close his/her results were.
Note: the smaller number of total grains in the cup or the longer the visitor spends counting grains,
the more accurate the result will be.
small jar with lid
timer or watch
pencil and paper
Scientist John Thorbjarnarson studies black caimans in the Amazon. These giant animals were once
endangered, but have made a comeback in recent years, and now they are widespread in the Mamirauá
Reserve. Part of Thorbjarnarson’s job is to know how many caimans there are. You can imagine that “a
few,” “tons” or “more than last year” is not enough information for a scientist, so how does he get
specific numbers? Maybe he could fly over the Reserve in a helicopter and count the caimans…or maybe
not; the area is twice the size of Delaware. Anyway, the caimans don’t stay in one place to be counted.
What John does to estimate the total number of caimans in the reserve is called a mark-recapture
sampling. Here’s how it works: he goes out into the field and catches as many caimans as he can in a
given time frame. He marks each one with a tag on its toe webs, then releases it and allows it to scatter
back into the overall population. After given time period (he decides this by figuring out how fast the
animal travels,) he does a second hunt. He counts up all the animals he is able to catch, and counts up
the marked ones. The ratio of marked to unmarked tells him something about the ratio of animals he has
caught to the animals in the population overall. For example, if nearly all the animals in his second catch
were marked, he would know that the population is very small. If only one marked animal turned up in the
second catch, he’d know that there are many more animals out there than he found the first time.
Now you’re almost there! The last thing you have to do is compare the size of your study area to the size
of the animal’s range. You multiply your population number accordingly, and that tells you how many
animals exist over the whole range.
Dry & Wet Seasons Coloring Pages
Visitors look closely at an Amazon River scene by coloring it.
Coloring pages of Karen Lybrand’s Amazon River dry and wet seasons
These images were drawn by artist Karen Lybrand to depict the landscapes, creatures, and plants of the
Amazon River. The images portray the same place on the riverbank, each at a different time of the year.
How can it look so different in the two images? The answer lies in the seasonal patterns of the equatorial
year. Unlike temperate areas, equatorial areas enjoy the same warm temperatures and equal 12-hour
periods of daylight and darkness. The one thing that changes is the rainfall. During the dry half of the
year, rain falls lightly in the Amazon. The soil is relatively dry, small streams and tributaries dry up, and
the water level in the rivers is low. During the wet half of the year, heavy rains pour down on the Amazon
basin, drenching the soil, running down hillsides, and flooding rivers and surrounding flat lands. As
rainfall changes over the course of the year, water levels can change by 30 feet! As you can see from the
pictures, a boat may float past the roots of trees during the dry season and reach halfway up their trunks
during the wet season. It’s hard to say exactly which months comprise each season, because it varies
from place to place, but roughly, winters are rainy and summers are dry.
Dry Season Riverbank: rich river mud left behind by the floods fertilizes the soil, allowing abundant
plant growth to feed animals like tapirs and coatimundis.
1. Lowland tapir: Tapirs are the largest land animals in South America. Although they have a
long, movable snout, they are related to horses and rhinos.
2. Coatimundi: This relative of the raccoon has a long, upturned nose and a ringed tail. It is an
omnivore and enjoys eating meat, fruits, insects, eggs, and leaves.
3. Greenwing macaw: Brilliant red parrots with long tails, they congregate in large flocks,
roaming the jungle in search of nuts, fruits, and seeds.
Wet Season Riverbank: The forest floor that tapirs and coatis walked upon a few months ago is now
under many meters of water. Fish swim among the trunks of the trees where birds had flown before.
1. Silver arawana, Osteoglossum bicirrhosum: this silvery, large-scaled fish grows to 3 feet. Its
eyes point upward, allowing it to see insects wandering around branches overhead. It can
even see clearly in water and in the air above at once! When it spots a juicy insect, it can
launch itself six feet out of the water to grab it.
2. Red-bellied piranha, Pygocentrus nattereri: this is the fish that most people think of when
their hear the name ‘piranha.’ There are actually many members of the piranha family, all with
different shapes, sizes, and diets. Red-bellies use their sharp teeth to eat other fish.
3. Red-tailed catfish, Phractocephalus hemioliopterus: this three-foot fish is occasionally seen in
aquariums. Its dark back and light belly form a color pattern called ‘countershading.’ This
pattern is great for sneaking up on prey or hiding from predators; the light belly blends in with
the surface when seen from below, and the dark back blends in with the bottom if you’re
looking at it from above.
4. Pirarucu, Arapaima gigas: This is the largest catfish in the Amazon, reaching 9 feet and 300
pounds. It thrives in low-oxygen water, taking breaths of air from the surface and using a
modified swim bladder as a lung.
5. Threespot headstander, Pseudanos trimaculatus: this fish is a member of a specialized group
of fishes from South America commonly known as headstanders. They keep a heads-down,
tails-up posture as they graze on algae and other food items on the river bottom.
6. Cardinal tetras, Paracheirodon axelrodi: this is the most common aquarium fish exported from
Brazil. Since the 1950s, more than 30 species of tetras have been collected for the ornamental
fish industry. They are a huge source of income to local people.
7. Flag prochilodus, Semaprochilodus insignis: this fish is known locally as Jaraqui. It feeds on
algae that grow on the trunks of trees in the flooded forest. Its pleasant tasting meat and
abundance have made it one of the most important commercial food fish in markets along the
8. Pirapitinga, Piaractus brachypomus: the pirapitinga lives in the floodplains of the Amazon and
its tributaries. It grows to 60 lbs and almost 3 feet in length on a diet of fruits and insects that
it finds in the flooded forest.
Sing a Song, Write a Poem
People express themselves through literature. Visitor can choose to read a selection of poems, songs, or
legends about nature and then compose one (written or oral).
Preparation: illustrated binder containing poems like limericks and haikus; including candirú song.
Some stories come from the radio and the TV, yet other stories are passed down through the generations
as families teach folk tales and songs to their children. Culture isn’t just handed down by the media –
everyday people play an important part in what kind of culture gets popular. In the Amazon, storytelling
is a vital part of people’s lives; stories are told and retold, passing from one generation to the next and
carrying accumulated wisdom with them. Thorough folklore, people learn about their history, about the
land around them, and its plants, animals, and spirits. Not everyone can read and write, so learning and
repeating folklore is a vital way to preserve regional culture. Songs are important too; people in Latin
America are just as likely to make their own music as they are to listen to the radio. Many people know
dozens of familiar songs, and have many opportunities to sing them at parties and festivals.
How many songs and poems do you know? A few? A dozen? A hundred? You may not read or memorize
poetry, but there are lots of songs, chants and rhymes that we learn; for example, how many of these
rhymes can you finish?
Find a penny, pick it up…
It’s raining, it’s pouring….
Rain, rain, go away…
Star light, star bright…
The eensy weensy spider…
Some of these are meant to make things happen, others help us remember things, some go with the
weather, and some make us laugh. Ogden Nash wrote many funny poems, particularly about animals,
The Eel The Termite
I don’t mind eels. Some primal termite knocked on wood
Except as meals. And tasted it, and found it good,
And the way they feels. And that is why your Cousin May
Fell through the parlor floor today.
The Python The Armadillo
The python has, and I fib no fibs, The armadillo lives inside
318 pairs of ribs. A corrugated plated hide.
In stating this I place reliance Below the border this useful creature
On a séance with one who died for science Of tidy kitchens is a feature,
This figure is sworn to and attested; For housewives use an armadillo
He counted them while being digested. to scour their pots, instead of Brillo
Edward Lear specialized in funny limericks. These are four-line poems where the first, second and last
lines rhyme on the last word, while the third line has a rhyme in the middle. It’s easier to read one than
There was an old man with a beard
Who said, “It is just as I feared!”
Two owls and a hen, four larks and a wren,
Have all built their nests in my beard.
A haiku is a three-line poem, usually about nature, that follows an ancient Japanese form. The first and
third lines have five syllables and the second has seven. These haiku are about the Amazon:
Droplets slide from leaves
that hang over a still pool
briefly sparkling. Drip… drip… plink!
Rings ripple outward
Something just fell in.
Who threw that? Monkeys?
Gentle curving tail
slipping silently along
propels a caiman.
Nature inspires many poems and songs. Why do you think that is? Maybe when people see something
amazing they want to find a way to describe it that is equally amazing. Here’s a song about nature, that is
not particularly beautiful, but certainly amazing: The Candirú Song.
Oh woe. oh woe, what can the candiru do to you?
A little fish in the amazon river
What awful pain it can deliver
They wait so long for the chance to pounce
It will hurt you right where it counts
So if you’ve really got to pee
Don’t do what happened to me
Here’s the truth, you’ll be glad i told it
If you’ve gotta go, you better hold it
Oh woe. oh woe, what can the candiru do to you?
Can you think of anything badder
To have a catfish gnawing on your bladder
If you’re swimming and you’ve got to go
This little devil will hit you from below
Your private parts are now his home
He will no longer have to roam
Rusty pliers won’t do the trick
You’ll need the doctor and mighty quick!
Oh woe. oh woe, what can the candiru do to you?
Wood You or Woodn’t You?
There are different ways to log wood from the Amazon. The demonstrator carries squares of different
woods to discuss logging and compare sustainable types with unsustainable types.
Amazon wood samples, such as:
Purple heart, Peltogyne spp.
Spanish cedar, Cedrela Odorata
Jacareuba, Calophyllum brasiliense
Jatoba(aka Brazilian Cherry), Hymenaea courbaril
Bubinga, Guibourtia spp.
Caoba mahogany (aka Honduran mahogany), Sweitenia macrophylla
Brazilian rosewood, Dalbergia nigra
Pau Amarelo, Euxylophora paraensis
Satinwood, Euxlophora paraensis
Tatajuba, Bagassa guianensis
Ipe, Tabebuia spp.
Bloodwood, Brosimum paraense
Timber tech sample
Other wood samples, such as spruce, pine, lacewood, and bamboo
Symbol of sustainably grown wood
Trees are a renewable resource, meaning that we can plant trees to balance the number that we cut down.
If we cut trees down faster than they can grow back, or if we cut down the last of a unique type of forest,
our use of trees is unsustainable. If we balance out the number of logged and replanted trees, and
protect trees that are irreplaceable, we can sustain the use of the forest over a long time. One way to
attain this balance is to grow trees on plantations where some sections are maintained as old-growth and
some sections are cleared and replanted, creating a patchwork of new and old trees.
Harvesting lumber from fast-growing, easily replanted trees is sustainable as long as you harvest at a rate
equal to or less than the rate at which they grow, but logging slow-growing trees with established old-
growth communities is not. Logging methods vary, too; some logging operations do more damage than
others. Taking out individual trees is less damaging than clear-cutting, where all the trees in an area are
cut down, including those that will not be used. In the Amazon, many types of large hardwood trees are
used for lumber, including purple heart, jatoba, bubinga, and mahogany. Fast-growing species are better
to use, as they can be grown on plantations or replanted in logged areas. One of the most sustainable
species is bamboo, which isn’t a tree at all! Bamboo is part of the grass family and grows incredibly fast,
sometimes inches a day; plantation-grown bamboo is ready to harvest after 6 to 8 years. Split and
processed bamboo stalks can be used for flooring like wood planks.
National governments, international alliances, and non-profit organizations work together to try to protect
the rainforest and make logging sustainable. CITES is an alliance that controls international trade, limiting
trade in species of plants or animals that are becoming scarce. CITES can ban the trade of a very rare
species, like Brazilian rosewood. This tree was so heavily logged that it was nearly wiped out, so it is no
longer harvested for lumber. In the case of more abundant species like Honduran mahogany, CITES may
restrict trade but not ban it altogether.
Other organizations, like the Forest Stewardship Council and Rainforest Alliance, may work with lumber
companies to improve logging practices by certifying wood as sustainable. Since buyers will pay more for
wood that is sustainably harvested, certified wood brings in a higher profit. To certify their wood,
companies have to replant cleared areas, keep from polluting water, minimize damage to surrounding
forest, and work with local communities. Rainforest Alliance has certified 1,000 logging operations over
32 million acres.
Print out images of the trees that these woods come from and discuss plant identification.