EvoDevo Ch. 1-3 Flashcards
Animal form is the product of what two processes and how are these processes related?
development from an egg and evolution from ancestors
development is the process in which an egg eventually grows into adult form and evolution of form occurs through changes in development
Theory of punctuated equilibrium
Idea that evolution is marked by long periods of stasis and interrupted by brief intervals of rapid change
“Evo devo” is short for what?
evolutionary development
What is the task of the “master” genes
control the formation and patterning of bodies and body parts
How did the discovery of developmental geneses change the way we think about animal relationships?
We can now see how different species formed and how they’re related, even if they don’t appear to be on the outside
Tool Kit Paradox
Paradox of great genetic similarity among diverse species
The development of a species depends on genes being turned on or off at certain times
where in the genome the “smoking guns” for evolution in form are found
First basic theme of animal design
related animals are made up of similar parts
Second basic theme of animal design
individual animals are made up of numbers of the same kinds of parts (like building blocks)
Modular architecture of animals
bodies are composed of similar, repeating parts
Bateson’s contribution to our understanding of animal form
He noted that animals differ in the number and kind of repeating parts
Homologs (and examples)
Same structure modified in different ways in each species
ex. forelimbs of salamandars, mice, and our arms
Serial homologs and example
structures that arose as a repeated series and have become differentiated to varying degrees in different animals
ex. hindlimbs, our legs, hind legs of four-legged vertebrates (with respect to each other)
Symmetry of animal form
most species have an axis of symmetry. This gives us clues as to how the animal was built
Polarity of animal form
head to tail
top to bottom (back and front in humans)
near to far from the body
teratogens
chemicals that cause monster-like mutations during embryonic development