The intervals:
- 2000 mya (2 billion years ago) -- the first -- calls and microscopic animals
- Eubacteria
- archaea
- eukaryocytes
- 900 mya (it took another billion years to get to plants)
- plants
- amoebozoans
- fungi
- drips
- choanoflagellates
- 630 mya (intervals are shorter; less than 300 million years to get to sponges)
- sponges
- placozoans
- ctenophores (look like, but are not, jellyfish
- acoelomorph flatworms
- 590 mya: deuterostomes appear (two sub-kingdoms: proterostomes and deuterostomes)
- 565 mya: a chordate shows up
- 530 mya ( only 100 million years to get from sponges to fish)
- pivotal: the dawn of vertebrates
- lampreys and hagfish
- 460 mya (but it took 70 million years to get to things that really looked like modern fish)
- sharks, rays
- 440 mya (the huge jump; only 20 million years to get to ray-finned fish)
- now we're cooking
- in quick order, ray-finned fish will break off and three major groups will appear
- coelacants (426 mya)
- lungfish (417 mya)
- everything else, sometime between 400 mya and 340 mya
- 340 mya: a little bit of a lag, from 565 to 340 million years ago, we finally get from "fish" to amphibians; that's a long, long time
- 310: Sauropods show up (once we get from fish to amphibians, things start to move quickly); after an incredibly long time where it as only fish or fish-like animals, it only took 30 million years to get from amphibians to reptiles;
- amphibians really were short-lived;
- then, again, a long time for the next leap while reptiles dominated;
- Permian: two dominant land land animals — sauropsids and synapsids;
- 252 mya: Permian Mass Extinction
- 180 mya (long period of mammal evolution begins, placental animals show up):
- first, monotremes showed up; and, then:
- 140 mya: the marsupials showed up;
- 25 mya: Old World monkeys; 100 million years to get from marsupials to monkeys)
- 4 mya: ape-men; Australopithecus
- 2 mya: Homo habilenes
- 160,000 years ago: "modern" or "nearly modern" man
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