Lecture 1 Flashcards
Symmorphosis
structure and function are optimally matched
Are there environmental or evolutionary or physical constraints on traits.
Yes
What are comparative biologists interested in?
How animals evolve, Environment changes, Learning something about our own physiology
Extant
species that are alive today - opposite of extinct
List of major environmental transitions
Salt to Fresh Water (and back again), Water to land (and back again), Wet to Dry Terrestrial Habitat:
Genotype
Inherited from 1 or more parents
Example of a self fertilizing hermaphrodite
The mangrove rivulus is one of several of “selfing” vertebrates.
Homologous structures
share a similar evolutionary path but may serve different functions, Descent with modification
Analogous structures
share a similar function but a different evolutionary path
Convergent evolution
Evolved similar functions as another based on environmental pressures - not same evolution
Evolution
change in the proportion of a population with a heritable trait over time
Four ways to change evolution
Gene mutations, Genetic drift, Gene migration / gene flow, Natural selection
Adaptations
a trait that evolved by natural selection
List of adaptations
Variable, Heritable, Confer a fitness benefit (reproductive / survival benefit)
Exaptations
traits that have been co-opted for a purpose other than what they were first evolved for natural selection
True or False: Natural selection acts on genes not phenotypes.
Natural selection acts on phenotypes not genes.
Vestigial structures
ancestral traits that are no longer useful
Is it true that “Not all adaptive traits are adaptations and not all traits that were adaptations are still adaptive.”
Yes
Describe adult phenotypic plasticity
a single genotype can produce multiple phenotypes in response to the environment
What is homeostasis?
using negative feedback allows animals to keep their internal environment constant
do all animals regulate their internal environment?
No
