3 traits of animals
eat other organisms, move, and multicellular
Sessile
fastened in place
Extant
exists, not extinct
Are some animals above / better than others?
No, all animal species exists because they successfully survive, reproduce, and adapt
4 main divisions of animals
no tissues (sponges) vs tissues, radial symmetry (cnydarians) vs bilateral (left and right), protostome+growing (flatworms, mollusks, annelids) vs proto+shedding (roundworms, arthropods), deuterostome (mammals, echinoderms/starfish)
Is Invertebrates vs vertebrates monophyletic groups?
No, product of convergent evolution
Chordates (vertebrates, tunicates and lancelets)
deuterostome, at some point have notochord (backbone), dorsal hollow nerve cord (brain and spinal cord), pharyngeal slit (gills), post anal tail
Are animals intelligent?
evolutionary adaptations but human iq should not be applied
How many species are there?
unknown anywhere between 3 million and over 100 million
Metamorphosis
larva (job is to eat), pupa (covers in casing, breaks body down, and resynthesized), adult (no eating, just reproduce), incomplete meta is nymph (small adult) to adult via molting, this and flight produced greatest adaptive radiation
4 adaptations for transitioning water to land
fins became limbs, vertebrae evolved to handle body weight and gravity, gills and swim bladders became lungs, amniotic eggs (wouldn’t dry out in air)
2 groups of terrestrial vertebrates
non-amniotes (amphibians) and amniotes (reptiles/birds, mammals)
Amphibians
water breathing kid, air breathing adult, most adults still lay eggs in water, kids live in water
Reptiles including birds
amniotes, birds are a branch of reptiles but can generate body heat (endotherms) and have feathers that were originally for attracting mates, while reptiles need sun and shade (ectotherms)
Mammals
hair and mammary glands, early mammals developed longer legs which made them more mobile and generated more heat, and hair trapped heat for temperature regulation, includes marsupials (viviparity/live birth, short development then pouch), placental (live birth, long development) and monotremes (eggs)
Evolution between humans and chimpanzees
humans became bipedal, the brain grew, and then the body (and brain) grew
Humans characteristics
forward looking eyes, 10 fingers and toes, shoulder/elbow joints, humans left trees to walk on ground, modern humans evolved around 200k years ago, three other species of humans went extinct 30k-12k years ago
