No Slide Title by nMYFuu3


									Evolutionary Ecology
Constraints to perfect adaptation
Mutations and genetic breeding in roosters
Gene Flow in Walleye
Walleye sampling sites
Walleye relatedness tree
Chimpanzee Hands And Feet -
tradeoffs between adaptations
         Drought Cycles in Iran –
Environmental conditions constantly changing
Phylogenetic Constraint – Egg Size
  and Brood Patch in Penguins
 Environmental or Genetic
Variation in WesternYarrow?
Creeping Bent Grass - Agrostis stolonifera
Adaptation in Trinidad Guppies
     Poecilia reticulata

                   Male and Female

Two males
Adaptation and natural selection in
       guppy populations

John Endler
Cline – Bergmann’s Rule
         Cline – Allen’s Rule

Arctic     Cool Temperate Warm Temperate   Desert
White clover – Trifolium repens
Cline in
by white
clover –
dark circle
white circle
lack cyanide
               Clinal variation in gulls

Herring Gull                Lesser Black-backed Gull
            What is a species?

• Morphological species concept:
  Assemblages of individuals with
  morphological features in common and
  separable from other such assemblages by
  correlated morphological discontinuities in
  a number of features.
                from Davis and Heywood
Rubus - Blackberries
   Biological Species Concept

Comte de Buffon        Ernst Mayr
          Biological species concept
A species consists of a groups of organisms which
  can sexually interbreed or at least have the
  potential to sexually interbreed (if geographically
  isolated) that are reproductively isolated from
  other such groups.

This is based on two criteria:
1. do populations from the same locality normally
2. if cross-fertilization does occur, are the hybrids
  viable and fertile?
                Sibling species

Species which look almost identical morphologically
  but which do not interbreed.

              Drosophila pseudoobscura
                   Gilia tricolor

Gilia angelensis
          Polytypic species
• Species made up of populations which
  differ morphologically but which will
  interbreed in nature.
Variation in Song Sparrows
   Potential problems with biological
             species concept
• Fossil species cannot be tested for
  reproductive isolation
• Asexual species also cannot be test for
  reproductive isolation – each clone is
  genetically separate from all others – Mayr
  calls asexual species ‘paraspecies’
      Phylogenetic species concept

• Species are defined based upon branching
  patterns in phylogenetic trees. Species are
  also defined based upon differences in
  evolutionary history. Species typically
  diverge when reproductively and/or
  geographically isolated.
Western and Florida Scrub Jay
• Speciation is the formation of new species.
• Allopatric speciation - formation of new species
  occurs when populations of a species become
  geographically separated from each other and
  diverge so that when they co-occur they cannot
• Sympatric speciation - occurs when reproductive
  isolation occurs within the range of a population
  before any differentiation of the two species can
  be detected.
 Allopatric Speciation –
Galapagos Islands Finches
Sympatric and Allopatric Speciation –
    Picture Winged Drosophila
Species of
Founder Events with Picture
   Winged Drosophila
Sympatric Speciation in Cichlids
Variation in Lake Malawi and
 Lake Tanganyika Cichlids
 Polyploidy in Spartina cordgrasses

• Polyploidy - an increase in the number of
  chromosomes beyond the typical diploid
  number - may be a doubling or greater - this
  happens most often in plants
• Polyploidy often occurs following the
  production of hybrids
Spartina alterniflora marsh – North Carolina
Spartina x townsendii
Spartina anglica – invasive in New Zealand

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