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Home , Biarmosuchus, Milleretta, Moschops, Tetraceratops, Titanophoneus

Meet the : The great terrestrial adaptation Pterosauria

Archaic archosaurs Crocodiles Dinosauria Lepidosaurs Most ‘amphibians’ Most ‘fishes’ Assorted jawless fish Amniota Urochordata Tetrapoda Cephalochordata Gnathostomata Vertebrata

Amniotic egg Chordata Thick skin Distinctive skulls The cleidoic egg: a private pond

Eggshell: Semipermeable Calcareous or leathery Albumen: Egg cytoplasm Amnion: Protection / Gas transfer Yo l k Sac: Nutrient Pool Allantois: Waste Pool Synapsida Anapsida Lepidosauria Archosauria

First amniotes Diapsida in record (!!)

Eureptilia

Amniotes Walking with Monsters Chapter 2 1:10-5:00 Evolution of Eggs?

Some modern amphibians To deal with longer time Eggs became larger, lay eggs on land... why? periods on dry land, tougher. Large eggs can - One inner membrane tougher shells were produce larger babies, 1. escape predation selected for. Gas exchange which had a higher and waste devices evolved likelihood of survival in a for complete eggtonomy tough world. Evolution of Hair?

Amniotes all have the gene for hair: alpha keratin In birds/, it’s expressed in claws In , it’s used in hair & nails 310 Ma

Thrinaxodon Blood vessel channels on premaxillae, maxillae ~vibrassae (whiskers) (early )

Castorcauda First direct fossil evidence of hair (mid-) Meet the Amniotes No temporal fenestra

Upper temporal fenestra Lower temporal fenestra

Single temporal fenestra = ‘window’ fenestra

The

299-251 Ma

The Permian

299-251 Ma Convergence of Pangaea

The effects of the landscape on climate: Gondwana icecap disappeared Heat distributed more equally through fluids than solids as continent drifted north Oceans slower to warm/cool than continents

Pangaea: Rapid warming/cooling ~ more intense than today Temperature extremes Our modern continents are ‘tempered’ by oceans between them. Not Pangaea Hot, arid terrains formed in the northern hemisphere ~Evaporite deposits Northern conifer forests Wetland plants mostly replaced by seed- bearing plants and conifers

Southern glossopterid forests: pteridosperms, or seed-ferns) A bit about seed-ferns:

- A paraphyletic group of seed-bearing extinct plants - Refer to members of a group that are fern- like & seed-bearing, but are not angiosperms, ginkgophytes, conifers, or cycadophytes (distinct by elimination) - Related to other seed plants - Flourished during , Permian - Declined during - They aren’t ferns Pterosauria

Archaic archosaurs Crocodiles Dinosauria Lepidosaurs Anapsids Synapsids Most ‘amphibians’ Archosauria Most ‘fishes’ Assorted jawless fish Amniota Urochordata Tetrapoda Cephalochordata Gnathostomata Vertebrata Chordata Synapsida Anapsida Lepidosauria Archosauria

Diapsida

Eureptilia

Amniotes Ecological Turnover: Exploit the dry land! Basal => amniotes

Milleretta

Capetus Captorhinus

Pederpes

Mesosaurus Pelycosauria (paraphyletic) Dinocephalia DicynodontiaGorgonopsia Therocephalia Cynodontia

Sphenacodontids Edaphosaurids

Theriodontia

Therapsida

Eupelycosauria Diapsida Synapsida Anapsida Amniota Eureptilia Pelycosauria -early Permian -most diverse group (70% of genera) -basal

Early : small, carnivorous Eothyris: early Permian -Large canine teeth Pelycosauria -most diverse group (70% of genera) -caseids

Herbivorous Pelycosaurs: large Cotylorynchus: mid-Permian -Largest -Peg-like Teeth -Enormous gut cavity -Angled Jaw Pelycosauria -most diverse group (70% of genera) -Varnopseids: small group of carnivorous Pelycosaurs (early Permian)

-Edaphosaurids herbivores (early Permian) Pelycosauria -most diverse group (70% of genera) -Sphenacodontids: Large Carnivores, early to mid Permian

Dimetrodon What’s the deal with the sail?

Sphenacodon

Lanthasaurus Poikilotherms

Platyhystrix (Temnospondyl) ? Contemporary of Pelycosaurs CONVERGENT EVOLUTION Walking with Monsters 11:58-18:06 Pelycosauria (paraphyletic) Dinocephalia DicynodontiaGorgonopsia Therocephalia Cynodontia

Sphenacodontids Edaphosaurids

Theriodontia

Therapsida

Eupelycosauria Diapsida Synapsida Anapsida Amniota Eureptilia •Basal •Dinocephalia -Late Permian •Dicynodontia •Gorgonopsids • Ancest.

Tetraceratops Basal Single prominent Canine tooth enlarged temporal fenestra reduction in palatal teeth •Basal Therapsids •Dinocephalia -Late Permian •Dicynodontia •Gorgonopsids Late Permian •Mammal Ancest. 40 genera Herbivores & Carnivores

Moschops Largest terrestrial of the time Placed hind legs directly under body Headbutting?

Titanophoneus •Basal Therapsids •Dinocephalia -Late Permian •Dicynodontia •Gorgonopsids ‘Pigs’ of the Permian •Mammal Ancest. Herbivorous Horny beak Enlarged temporal fenestra

Wadiasaurus

Lystrosaurus Kingoria

Placerius •Basal Therapsids •Dinocephalia -Late Permian •Dicynodontia •Gorgonopsids •Mammal Ancest.

Arctognathus •Basal Therapsids •Dinocephalia -Late Permian •Dicynodontia •Gorgonopsids •Mammal Ancest.

Cynodontia

Hey Great*107 Grandma! Synapsida Anapsida Lepidosauria Archosauria

Diapsida

Eureptilia

Amniotes Anapsids -Late Permian -Vegetarians

Scutosaurus