生物适应与进化英文版.ppt

BIOL 4120: Principles of Ecology
Lecture 2: Adaptation and
Evolution
Dafeng Hui
Office: Harned Hall 320
Phone:963-5777
Email: dhuiatnstate edu
Evolutionary Ecology
Nature selection as a force of evolution
2. 2 Herita bility is the feature of Natural
Selection
2. 3 Genes are the units of inheritance
2. 4 Genetic variation is the ingredient of Ns
Evolution is the outcome of ns resulted
om gene frequency change
Speciation and mechanisms
Introduction to evolutionary ecology
Major question in Ecology: What determines
distribution abundance of species?
Two classes of answers
Contemporary, local factors(domain of
traditional Ecology biomes and PPT and
Historical factors(- evolutionary ones)
Why different species live in different
environments?(Adaptation
., long necked giraffe in savannas of
Africa(widely dispersed, umbrella
shaped trees); white coated polar bear
in arctic(invisible to prey)
Nature selection as a force
of evolution
What is darwin's natural selection?
The differential success(survival
and reproduction) of individuals
within the population that results
from their interaction with their
environment
Survival of fitness, elimination of
inferior'individual
Two conditions(assumptions)
1. There is variation in populations, Variation is
heritable
2. In every generation some organisms are more
successful at surviving and reproducing than others
Survival and reproduction are not random, but are
related to variation among individuals. Organisms
with best characteristics are naturally selected
If 2 conditions are met then the population will
change from one generation to the next Evolution
will occur
Evidence of natural selection
Evolution of beak shape in Finches
Peter and Rosemary grant's(and
colleagues)work on Medium Ground
Finches Geospiza fortis.
Natural
selection
a Darwin's
Finches
Large Tree Finch
oxpecker Finch
a Genetic
(Insects)
studies show
all arise fr