Please enable JavaScript.
Coggle requires JavaScript to display documents.
End Permian Life Change 2 (Archosaurs Appear (On both croc & bird…
End Permian Life Change 2
Disaster Species
Some animal species became
very common
Could deal well with change / survive well in chaos
Lystrosaurus
Very abundant near everywhere
pig-like reptile
Early Triassic as eruptions continued
Thrived in disequilibrium
Declined once ecosystem recovered
Why? mixed diet / smallish size / burrowers?
Tetrapods
after End Permian
some wiped out
some survived
some thrived i.e. lystrosaurus
Archosaurs Appear
Appeared after volcanism ceased
Flourished
- lotsa species & body types
Remaining archosaurs = birds, crocodiles
On both croc & bird lines of descemt
Crurotarsi = crocodile line
Aetosaurs
Phytosaurs
Avemetatarsalia = bird line
Pterosaurs
Basal dinosauromorphs
Terrestrial life took > 5Ma to recover
Establishment major modern tetrapod groups
Once ecosystem recovered & volcanism ceased
e.g. salamanders, lizards,
Marginal (uncommon) to begin with
During Early Triassic ~ 5 Ma after End Permian
Rise of Archosaurs
Origin - soon after volcanism began
Rare & small footprints
Rare - boom/bust cycles
Rise once volcanism ceased
skeletons in fossil record
Archosaurs more common & diverse
Archosaurs dominate Triassic
Recovery
End-Permian
What types of species / groups around as Earth recovered ?
Holy Cross
Mtns
, Poland
Near continuous record from Permian - Triassic - Jurassic
Abundant sedimentary rocks - mudstone, sandstone
Footprints
~250Myr
with 2 main toes
Inner/outer toes = small
Many types
Prorotodactylus = 5%
oldest dinosauromorph
oldest dino ancestor
Small, sleek, fast runners
When volcanism still going
Rare Skeletal
Body Fossils
Ctenosauricus
Oldest archosaur/croc
~247 Ma when
volcanism waning
Skeletons = sign more animals around
greater chance of preservation