Intro STUFF Flashcards
transitional species
can only be identified retrospectively
- bc we know the lineage later evolved
evolution of mammals
therapsids to cynodont to mammals
morganucadon
early mammalian form
205 mya
hadrocodium wui
195 mya
derived ear structure: separation of middle ear bones from the jaw.
developmental biology
important tool for reconstructing paths of change and understanding a genetic change that leads to a change in phenotype
-tells us about homologous characters
tiktaalik
- another morphological bridge between lobe-finned fishes and tetrapods
- gills, scales, and fins like a fish but flat head and eyes. nostrils on top and a neck
- limb bones (with wrists)
heterochrony
evolutionary change in timing or rate of developmet
paedomorphosis
having juvenile attributes while being a sexually mature adult
peramorphosis
phylogenetic change in which individuals of a species mature past adulthood and take on hitherto unseen traits.
pseudogenes
organisms retain genes for making structures no longer found in their lineage
biological species
- defined by reproductive isolation
- largest unit of population in which successful reproduction is possible
a rooted phylogenetic tree
base is located at the common ancestor of all taxa depicted on that tree.
fossill record goes back
3,500,000,000 years ago