week 7 Flashcards
what did cyanobacteria do
evolve photosynthesis and formed stomatolites in proterozoic and some became chloroplasts for algae
what did eukaryotes do
captured their chloroplasts
where did land plants evolve from
within charophytes (group of green algae)
what is a major event in terrestial ecosystem evolution
late silurian - small vascular plants such as cooksonia
when did insects and tetrapods and forests with horsetails appear
devonian
the massive radiation of insects, forests with ferns and seed plants began when
carboniferous
forests with seeds ferns and gymnosperms appeared when
permian
frogs, turtles, pterosaurs, dinosaurs and stem mammals appeared when
triassic
the jurassic was characterised by
angiosperm pollen, origin of crown group mammals
what happened in the cretaceous
angiosperms displaced gymnosperms and the first birds appear
when did modern insects, plants, birds and mammals appear
palaeogene
when did megafaunal extinctions occur
neogene with global cooling and biotic homogenisation
what is a tetrad
a spore in the ordovician that was moss like (bryophyte) non vascular
what are the 4 major groups of vascular plants
lycophytes (no seeds)
ferns (no seeds)
gymnosperms
angiosperms
what are the outgroup of ferns and seed plants
clubmosses
spikemossess
quillworths
are true mosses vascular?
no
what were mid to late palaeozoic trees
lycophytes (no seeds)
how did leaves evolve
from ferns and seed plants in microphyll and megapyll evolution
whats the difference between microphyll and megaphyll evolution
simple leaf structure vs complex leaf
what are ferns characterised by
megaphylls, fronds borne on a trunk and spore bearing enclosures under the leaves
what did the devonian ferns evolve
complex vascular systems
what did rhyniophytes have and when did they exist
during the silurian and devonian, they had simple branches and sporangia but no leaves or roots
in the devonian when the CO2 dropped and O2 rose, what caused the mass marine extinctions
global cooling
what characterises primitive pterosaurs
long tails, smaller body size like a modern bird
what characterises derived pterosaurs
large size range from very large to modern bird size.
what clade is dinosaurs
ornithodira
what happened in the PETM
migration of primates and plants north
evolution of small body size in mammal
what was no characteristic of south america before great american interchange
mammthos and mastodoons
what are whales and who are they closely related to
they are even toed ungulates related to hippos.
what was vegetation stage 0
archaen eon when there was no evidence of vegetation in terrestial realm
where did land plants evolve from
within charophytes (green algae)
when were the earliers land plant macrofossils found
in the silurian and early devonian
describe the microphyll evolution
intially, there is a vascular tissue with a protuding scale. then a simple leaf grows into that scale
how many fern species are thee
12,000 species
what key plant adaptation changed ecosystems in the devonian
stronger tissues
vascular systems
leaves
stomata
roots
seeds
what environmental conditions changed ecosystems in the devonian
less atmospheric Co2
more O2
forest canopies
deep soils
leaf litter
when did terrestial arachnids evolve
devonian
what is a key terrestial lagestatte in the early devonian
Rhynie Chert, the fossiles preserved in siliceous hot spring deposits. they are the oldest vascular plants and oldest insects
what is the oldest insect
rhyniella praecursor
what is the closest living relative of tetrapods
lungfishes
when did the transition from fish to tetrapod happen
devonian
what characterised carboniferous and permian
seed ferns, swamps, large radiation of insects (due to evolution of flight)
when did amphibians (frogs) and amniotes (reptiles) split
carbonifeous
when did the reptiles and synapsids (amniotes) split
carboniferous
what did the synapsids lead to
mammals
what was characteristic of triassic amphibians
larger size
when did modern amphibians split
late carboniferous
what is the order of groups that lead to mammals
synapsids > therapids > mammals
what are gymnosperms
group of seed plants such as cycads, gingkos
what are the 4 major groups of gymnosperms
conifers, cycads, gingko and gnetophytes
characteristics of conifers
adapted to cold, dry climate (not podocarpaceae and araucariaceae
needle like leaves with thick cuticles
seeds within tough scales
scales arranged in cones
what were mesozoic forests dominated by (vegetation)
dominated by conifers
when did moths, flies, wasps (holometabola) radiate
in the triassic
when did the first frogs, turtles ichthyosaurs appear
triassic
when did dinosaurs appear, radiate and what group
triassic in the ornithodira clade, and during the late triassic after the carnian-norian boundary
why were dinosaurs rare through triassic
because other mammals, inverts existed and dominated
what lagestatte is key in the cretaceous
chinas jehol group in northeast china as it preserves complete ecosystems
what is the most common fossil in the jehol group
birds
what are the 3 vertebrates that evolved true flight
bats, birds and pterosaurs
what clade does angiosperms largely make up
fruit and flowers
when were the oldest certain angiosperms
early cretaceous
what happened after the K-Pg extinction in terms of isolation
4 large regions were isolated
> Australidelphia
> afrotheria
> Xenarthra
> Euarchontoglires + Laurasiatheria
what happeend in the palaeocene eocene boundary
PETM - global warming event which impacted plants, mammals evolved smaller body sizes and northward migration of animals and plants
