17.4
Macroevolution large scale evol. Patterns Extinction more than 99% of org. that were, are not
Extinction Mass extinction food webs wiped out cretaceous period- huge asteroid Most mass extinctions several causes
Adaptive radiation Several species can evol. From one species ex: darwin’s finches (13 species from 1)
Convergent evolution unrelated org. react to similar env. And evolve to look very alike Ex- many unrelated aquatic species have similar body shapes
Coevolution org. that are evolving in response to each other Flowers and insects (pollinators) Ex- orchid changed to have pollinator 40 cm down the flower--- insect with 40 cm structure to get nectar
Punctuated equilibrium unlike what Darwin thought (slow changes) there is a time with no change and then period with a lot of changes
Changes in dev. genes/body plans One change in one gene can turn on or off dif. Characteristics Ex- ancient insects wings on all segments, modern insects have one segment with wings