Standard Grade Biology Topic 3 Animal Survival Animal Survival is divided into: A- The need for food B- Reproduction C- Water and waste D- Responding to the environment What changes? The environment has many places called habitats (such as land, sea, in the air and in water). Animals or plants live there with the conditions they need to survive. Organisms need to be able to detect and respond to a stimulus or change in those surroundings. Detecting Environmental Factors Why? To improve their conditions (hence survival chances) or protect themselves from harm. Humans have many sense organs to detect stimuli What do you think you can detect? How does your body do it? Lets do some experiments….. Sight Sense Stimulus Sense organ Sight light eyes Smell Sense Stimulus Sense organ Smell chemicals nose Skin Above- surface Left- cross-section Sense Stimulus Sense organ Temperature heat / cold skin Pain damage skin Pressure force skin Touch contact skin Hearing, balance Sense Stimulus Sense organ Hearing sound ears Balance movement part of inner / position ear Taste Sense Stimulus Sense organ Taste chemicals tongue and throat Vertical section through human tongue; a, a, blind lymph capillaries in the filiform papillæ with the underlying lymphatic plexus. X 45. (Teichmann, 1918.) Case Studies We will look at some different species, find out what the stimulus is, how they respond, and the importance of it to the animal’s survival. Woodlouse Blowfly maggot Shore crabs Hedgehog Cockroach Barnacle goose Atlantic salmon We will also look at how scientists find this out… Choice Chamber A choice chamber is a piece of apparatus that lets a scientist study the effect of differences in an environmental factor on the behaviour of an animal. Different conditions can be set up in different sections of the chamber. The proportion of time that the animals spend in each area can be measured. Hence their preferred conditions can be determined. Woodlouse choice chamber Woodlice move randomly. IN Those in the light respond by moving quickly. Why? This increases their chance of moving out of the light and into the dark. Those in the dark Why? This behaviour respond by moving increases their chance of slowly or coming to staying in the dark. a standstill. Woodlouse response Stimulus Moisture Dark Response Moves towards Slows & stops moisture in dark places Importance to survival In dry conditions they lose When in light, easily water through their spotted & eaten by permeable skin & die predators Blowfly maggot The name comes from an older English term for meat that had eggs laid on it, which was said to be fly-blown. Their common name is blue-bottles. They are usually the first insect to come in contact with a dead animal. Blowfly Fact File Natural life history largely unresearched Adults are occasional pollinators, attracted to flowers with strong odours resembling rotting meat Larvae are scavengers of carrion and dung Rate of development is highly dependent on temperature eg. Black blowfly egg to pupa takes 6 – 11 days, it leaves corpse, burrows into ground and emerges as adult after 7 – 14 days….. If ambient temperature is known they are used in forensic science to estimate the time of death (rigor mortis unreliable after 72 hours). Used to treat badly infected wounds Gladiator Blowfly reproduction Eggs about 1.5 mm x 0.4 mm, are yellowish or white, look like rice balls. Typically lay 150-200 eggs per batch, but around 2,000 eggs during the course of her life. The sex ratio of blowfly eggs is usually 50:50, but females from two species of the genus Chrysomyia (C. rufifaces and C. albiceps) are either arrhenogenic (laying only male offspring) or thelygenic (laying only female offspring). Blowfly maggot response They have no eyes Stimulus yet can detect & respond to light! Light Response Moves away from light Why? Importance to survival They hatch from eggs Needs to stay in dark laid in manure heaps and places to obtain food, in animal corpses. moisture, shelter and protection from predators Sense / response Questions 1. How are changes in your environment detected? Through your senses sending signals to the brain 2. Name 3 environmental factors that organisms can respond to. Light, humidity/moisture, chemicals 3. Describe three examples of responses to stimuli. Woodlice stay in dark& moisture, cockroaches stay in dark, human response to pain etc 4. Explain the advantages of the responses which you described in your answer to question 2. Woodlice avoid predators/can breathe, cockroaches avoid predators, human prevent further harm/damage 5. For a named organism, explain the significance of a response it makes to a stimulus. Woodlice & cockroaches who avoid predators stay alive and survive Rhythmical behaviour What is it? When animals alter their behaviour in response to a change in environmental conditions (a trigger stimulus). Main features: It is regular It is triggered by an external stimulus It possesses an internal component which causes it to persist even in the absence of the trigger stimulus (biological clock) You got rhythm? Why have it? Allows organism to exploit regular events in the environment and increases its survival chances. Rhythmical behaviour can occur: Daily (occurs once every 24 hours, or at the same times of day) Monthly Annual / Seasonal (daylength, temperature) Tidal (occurs at each turn of the tide, each complete cycle takes 12.5 hours) Daily rhythms- examples Sun’s position & movement during the day Night/day (active during day- diurnal, at night-nocturnal) Movement of leaves/flowers during constant light Insects emerge from pupae at a particular time of day In internal organs and cells, the release of enzymes & hormones vary during the day Watch Planet earth sequences- Ice world- penguins, Deep oceans- Blue whale Rhythmical Behaviour Shore crabs You may have met them on the beach in rock pools… Read workbook p94, 95 1. Write a note on how the crab’s activity is related to the movement of the tide. 2. Identify the trigger stimulus. 3. Explain what happens to the crabs’ pattern of activity when placed in constant laboratory conditions. Shore crabs Rhythmical behaviour pattern High activity at high tide Trigger stimulus Tidal Importance to survival Food available at high tide (small seashore animals). This is when they become very active and feed Hedgehog Name used from 1450’s, derived from the middle English word 'heyghoge'. Other folk names include ‘urchin’, 'hedgepig' and 'furze-pig'. There are 16 species, native to parts of Europe, Asia and Africa. They have changed little over 15 million years and have adapted to a nocturnal, insectivorous way of life. Hedgehog fact file Pest control- …but by eating They also a hedgehog them it can take in feed on eats up to 200g chemical insecticides snails, frogs, insects a night! and may poison itself toads, snakes, bird …but they eagerly eggs, carrion, eat foods that are mushrooms, high in fat and sugar grass roots, instead of low-fat, berries, protein-rich insects. melons, They are also lactose- watermelons, intolerant. earthworms after rain! Eating these foods can lead to obesity, a fatty, damaged liver and heart disease. Can become pests where they have been introduced by man eg. North Uist and Benbecula as they have no natural predators & eat bird’s eggs. Predators in forest: birds (esp owl), ferrets Smaller long-eared hedgehog predators: foxes, wolves, mongooses Lifespan 4 – 7 years in the wild (record 16) Communicate with grunts, snuffles and some species use loud squeals Defence: rolls into a tight ball, causing all of the spines to point outwards Desert hedgehogs run away, or attack intruder by ramming it with its spines, ball last resort! Hedgehog Sleep for a large portion of the daytime either Rhythmical behaviour under cover of bush or pattern grass or rock or in a hole in the ground, generally Hibernation dig out dens for shelter. Trigger stimulus Decreasing daylength and temperature Importance to survival Conserves energy when food is in short All wild species have the supply (over winter) ability to hibernate… Cockroach Common household roaches A. German cockroach, B. American cockroach, C. Australian cockroach, D&E. Oriental cockroach (♀ & ♂) Largest is C which grows up to 9cm long, 30g weight. They are mainly nocturnal and run away from light. Men in Black Exception is Oriental (D&E) chapter 26 which is attracted to light. Cockroach fact file In buildings they often die on their backs as they cannot grab hold of something with their legs and turn Could be one of the few species to survive a nuclear blast as they bury themselves underground and… Radiation lethal dose is 90K – 105K rems for German cockroach, 800 rems for a human (16 life) Can survive 1 – 4 weeks without a head- breathe through spiracles in body, don’t control it with their brain, don’t need blood like a human and… Survive on very little food- up to a month without any! Can eat the glue from the back of stamps If you have a shellfish allergy, you are likely to be allergic to eating cockroaches Predators Lifespan Reproduction only a few development from German including egg to adult takes cockroach birds, bats, 3-4 months. Adults carries an egg house live up to a year capsule centipede, containing wasps, small around 40 eggs. animals In favourable conditions 1 female may produce 300- 400 offspring Other cockroach species have 100 eggs in a sac, only need to be inpregnated once to be able to lay eggs for rest of lifespan- up to 1 million offspring Cockroach Rhythmical behaviour pattern Night activity (nocturnal) Trigger stimulus Darkness Importance to survival Less chance of being caught by predators when feeding at night Annual rhythms More about courtship and hibernation… Read workbook p97. Watch Biovideo 63 Sexual reproduction in animals, ‘internal fertilisation’ Use both sources of information to write notes on: 1. 3 features they have in common to be true rhythmical behaviours. Regular, trigger stimulus to start if no trigger-continues at expected time 2. The environmental trigger stimulus that brings about courtship in the great crested grebe and the red deer. Daylength (grebe- increasing, red deer-decreasing) 3. The environmental trigger for hedgehog hibernation. Decreasing daylength and temperature 4. The survival value of all these behaviours. Increased chance of reproducing, and offspring surviving. Hedgehog- Energy conservation when little food available Biological clock These rhythms can all operate independently of external conditions even if all the stimuli have been removed. This shows that organisms have an internal biological clock. The biological clock is adjustable and can be triggered by external stimuli. We will look at the biological clock and some circadian rhythms in humans… The word circadian comes from circa diem (Latin) "about a day". Circadian rhythms The circadian "clock" in humans is located mainly in the hypothalamus (brain) The circadian rhythms determine human sleeping patterns and… there are patterns of brain wave activity, hormone production, cell regeneration, and other biological activities linked to this 24-hour cycle. Factors outside the body, especially bright light, help to set the internal clock to the day cycle or time schedule appropriate to where the person is. Human circadian rhythms Temperature Growth hormone Cortisol Urinary potassium Rhythm Problems In a person with a circadian rhythm sleep disorder, the body is unable to maintain its normal rhythm. The natural sleep schedule changes so that the person is out of phase with day and night. We can all be affected by: Shifting into or out of British summer time Travelling across time zones (jet lag) Shift work that involves late evening or night-times Plant Circadian rhythms Regulate metabolic activities such as photosynthesis, moving leaves and flowering. They run on an approximately 24 hour period. The internal biological clock enables the organism to anticipate the needs of the day in good time to prepare for them. Eg. Open flowers at night if you are bat-pollinated, during the day if you are bird- or bee-pollinated. Grandidier’s Baobab tree, and Madagascar fruit bat (Eiodolon dupreanum) which pollinates them at night-time. Biorhythm questions 1. What is meant by a trigger stimulus? 2. Describe three examples of rhythmical behaviour. For each one identify the trigger stimulus. 3. Describe what is meant by a ‘biological clock’ 4. Describe the type of advantage gained from most rhythmical behaviours. 5. Explain why the midge larvae in a pond tend to change into flying adults at nearly the same time on the same day. What is the advantage for the midges? Planet earth sequence, Forests- insects Annual rhythms Migration We will look at 2 animals that migrate and consider the advantages of this type of behaviour to them: Barnacle Atlantic goose salmon Watch Incredible journeys - Osprey Barnacle geese Vital Statistics Branta leucopsis Eggs: 4-5 Incubation: 24-25 days Fledging: 40-45 days Maximum lifespan: 18 years Length: 58-70cm Wingspan: 132-145cm Weight: 1300-2200g Eat leaves, roots, stems,seeds UK breeding: 1,000 birds UK wintering: 60,000 birds Flies in packs and long lines, with a noisy chorus of barking or yapping sounds Where are they? In winter, Islay holds 70 % of the world's Greenland barnacle geese (37,000) and 40% of the Greenland white-fronted goose population (13,000). The RSPB bought the land at the head of Loch Gruinart in 1984. This area holds one of the main barnacle goose roost sites and some of the most important feeding areas for barnacle geese and white-fronted geese. Many in Solway firth too, They are seen in UK between October & March. Barnacle goose Rhythmical behaviour pattern Migration Trigger stimulus Increasing daylength Importance to survival Breed in Iceland to escape predators, migrate to Scotland in winter for food Workbook- Barnacle goose Read workbook p96 and collect sheet G2 migration 1. What are the environmental conditions that affect the lives of Barnacle geese in the two places it inhabits? 2. Identify the trigger stimulus 3. Why does migratory behaviour increase the survival chances of the Barnacle geese? Canadian goose in the Atlantic flyway Then read workbook p105 and answer the questions Atlantic salmon Vital Statistics Salmo salar Live up to 8 years Average weight 3.6 –5.5kg Develop bright hues around spawning times Females lay up to 20,000 eggs in October-November Flesh often orange-red Record catch- 38kg Eat smaller fishes, crustaceans, and insects. They are found in both fresh and salt water in the colder regions of the northern hemisphere. Salmon migration Adults migrate hundreds or thousands of miles from the sea into cold fresh water in late spring or early summer. They swim upriver (up to 4 miles per day) to spawn in exactly the same places as the generation before. During the migrations and nest-building activity that precede mating, neither the females nor the males consume food. Migration routes- Atlantic salmon The salmon fishing industry is one of the major industries of the states along the American Pacific coast, providing 60,000 jobs and more than $1 billion in income per year for the region However, some experts have raised concerns about hatchery-raised salmon because they compete with wild salmon for food and are more vulnerable to predators than are wild salmon. In addition, hatchery salmon usually have less genetic diversity than wild salmon, Salmon life cycle The eggs hatch in 2 weeks to 6 months, depending on the species and the water temperature. Salmon develop from alevins to fry and emerge from the gravel. Eventually turn bright silver (smolts) and descend to sea. When they are fully grown and reach sexual maturity, the salmon begin the migration back to fresh water to reproduce. Atlantic salmon Rhythmical behaviour pattern Migration Trigger stimulus Increasing daylength Importance to survival Breed in Scotland, migrate to Atlantic coast of Greenland for rich feeding grounds Workbook- Atlantic salmon Read workbook p96 and collect sheet G2 migration 1. What are the environmental conditions that trigger migratory behaviour in the young salmon in the fresh water river? 2. What triggers migratory behaviour in the adult salmon in the seas and oceans? Then read 3. Why does migratory behaviour workbook p104 increase the survival chances and answer the of the Atlantic salmon? questions Summary questions 1. Why is it important that animals respond to changes in their environment? The conditions an animal chooses are usually the best for its survival 2. Why do blowfly maggots move away from the light? By staying in dark places they are more likely to obtain food & protection 3. Explain the why the response of woodlice to environmental stimuli increases their chances of survival. They move to where it is damp where they can breathe easier 4. What is rhythmical behaviour? Behaviour of animal in response to regular changes in the environment 5. What is meant by a trigger stimulus? An environmental condition or change that sets off a behavioural response 6. Give an example of rhythmical behaviour shown by hedgehogs, what is the trigger stimulus? Decreasing day length and temperature Extensions Bird migration Wordsearches- reproduction, water workbook p102 balance. Bird migration PS data and Q Crossword- reproduction Project on rhythmical behaviour- ask to see S3 March 2006 powerpoint presentation for ideas & book Suggested weblinks: Bird Migration- why they do it and how http://www.wwtlearn.org.uk/index0.html?factfile/migration.htm&2 Salmon fact file and link to conservation organisation at arkive.org Major conservation issues in pacific north-west USA. msn encyclo. Textbook Torrance, SG Biology, p121 Look at the table which gives examples for various rhythmical behaviours including tidal (green flatworm, fiddler crab) Draw up a table with the headings: type / animal / description of rhythmical behaviour / external trigger stimulus / significance Type Animal Significance Copy it and add in the ones we have studied in this topic to summarise the behaviours.