iv. cenozoic (65 - 0 mya). the major groups of mammals had evolved in the jurassic and cretaceous
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IV. Cenozoic (65 - 0 mya)
IV. Cenozoic (65 - 0 mya)
IV. Cenozoic (65 - 0 mya)
The major groups of mammals had evolved in the Jurassic and Cretaceous.
IV. Cenozoic (65 - 0 mya)
IV. Cenozoic (65 - 0 mya)
The extinction of the dinosaurs opened many niches, but the mammals were hammered by extinctions, too.
IV. Cenozoic (65 - 0 mya)
The extinction of the dinosaurs opened many niches, but the mammals were hammered by extinctions, too. Small mammals, however, quickly radiate into most ecological niches except large predators.
IV. Cenozoic (65 - 0 mya)
In the absence of dinosaurs, the birds radiated:
Diatryma (Gastornis) in NA/Asia
seed eater?
IV. Cenozoic (65 - 0 mya)
In the absence of dinosaurs, the birds radiated:
Phorusrhacids in SA: Top Predators
IV. Cenozoic (65 - 0 mya)
In the absence of dinosaurs, the birds radiated:
Phorusrhacids in SA: Top Predators
Largest one yet, found in Argentina in Oct. 2006, probably stood over 10 feet tall.
Chiappe and Bertelli. 2006. Nature 443:929.
2.3 ft
condor
IV. Cenozoic (65 - 0 mya)
MAMMALIAN RADIATIONS:
IV. Cenozoic (65 - 0 mya)
The nature of these radiations varied on the different, separated continents
IV. Cenozoic (65 - 0 mya)
The earliest marsupials evolved in North America, but the were practically wiped out there at the K-T. They didn't recover in NA, but weathered the K-T (and ultimately dominated the fauna) in the southern supercontinent of SA, Antarctica, and Australia, eventually radiating into all ecological niches.
late Cretaceous Alphodon, a Didelphiformian (common marsupial group)
IV. Cenozoic (65 - 0 mya)
The earliest Cenozoic marsupials are in SA (Paleocene), but by the Eocene they are present in Antarctica and Australia. They begin as insectivores...
Argyrolagus (SA)
IV. Cenozoic (65 - 0 mya)
then radiate as large herbivores (in Australia, primarily)...
Diprotodon
IV. Cenozoic (65 - 0 mya)
and finally radiate as top predators.
Thylacoleo
Marsupial "Lion"
(Australia)
'cat-like'
IV. Cenozoic (65 - 0 mya)
and finally radiate as top predators.
'cat-like'
Thylacosmilus (SA and Australia)
IV. Cenozoic (65 - 0 mya)
and finally radiate as top predators.
Borhyaena (SA)
'Dog-like'
Thylacine (Australia)
IV. Cenozoic (65 - 0 mya)
In the isolation of Australia, they radiated to fill all mammalian niches:
Insectivore
Fossorial
“teddy bear” niche 45 species of terrestrial
herbivores (Wallabies and Kangaroos
Nectarivore
Honey Possum
IV. Cenozoic (65 - 0 mya)In the isolation of Australia, they radiated to fill all mammalian
niches:
Arboreal Glider Arboreal Herbivore/Frugivore
brush-tailed Possum
IV. Cenozoic (65 - 0 mya)In the isolation of Australia, they radiated to fill all mammalian
niches:
'cat-like'
Predator
Quolls (several species)
IV. Cenozoic (65 - 0 mya)In the isolation of Australia, they radiated to fill all mammalian
niches:
'dog-like'
Predator
IV. Cenozoic (65 - 0 mya)In the isolation of Australia, they radiated to fill all mammalian
niches:
Omnivore/Scavenger
Tasmanian Devil
IV. Cenozoic (65 - 0 mya)
In SA, in addition to the marsupials, there were placental mammals - but only radiating as large herbivores:
Toxodon
IV. Cenozoic (65 - 0 mya)
and a notable mammalian clade, the Xenarthans - Sloths, Armadillos, Anteaters - were diverse and abundant in SA faunas:
Megatherium
Glyptodon
Xenarthans – a very primitive mammalian clade
IV. Cenozoic (65 - 0 mya)
and an Africarabian fauna evolved in isolation on Africa/Arabia - the modern group called that Afrotheria:
Aardvarks
Tenrecs
Hyraxes
Elephants
Elephant Shrews
Golden Moles
Is the Afrotheria polyphyletic?(1995)
Kriegs JO, Churakov G, Kiefmann M, Jordan U, Brosius J, et al. (2006) Retroposed elements as archives for the evolutionary history of placental mammals. PLoS Biol4(4): e91.
A more recent genetic analysis says no… (2006)
Curiously, this places the Pangolins (Pholidota) with Carnivores.
IV. Cenozoic (65 - 0 mya)
- Paleocene (65-55 mya)
The multituberculates dominated the "rodent niche" in northern continents. Ptilodus
IV. Cenozoic (65 - 0 mya)
- Paleocene (65-55 mya)
The first large herbivores were Pantodonts... including Titanoides and Coryphodon. There are few direct adaptations to an herbivorous lifestyle
Ptilodus
IV. Cenozoic (65 - 0 mya)
- Paleocene (65-55 mya)
The next clade of mammals were the Condylarths – omnivorous ancestral to the modern ungulates (Artiodactyls and Perissiodactlys).
Phenocodus
IV. Cenozoic (65 - 0 mya)
- Eocene (54-38 mya)
Many modern groups evolve in the northern continents:
Artiodactyls and Perrissiodactyls replace condylarths
proto- horses (Hyracotherium), tapirs, rhinoceroses, and camels, and bats, primates (Purgatorius), and whales (Basilosaurus) evolve.
Mesonychid (a condylarth)
Ambulocetus
Pakicetus
Basilosaurus
IV. Cenozoic (65 - 0 mya)
- Eocene (54-38 mya)
Icaronycterus index
IV. Cenozoic (65 - 0 mya)
- Eocene (54-38 mya)
First Primates - Plesiadapids
(Paleocene)
Purgatorius
IV. Cenozoic (65 - 0 mya)
- Eocene (54-38 mya)
Many modern groups evolve in the northern continents:
creodonts replaced large birds as major predators
IV. Cenozoic (65 - 0 mya)
- Oligocene (38-24 mya)
a cooling period, creating savannahs - grazers and browsers radiate
Mesohippus
Calicotherium
grasses evolve
IV. Cenozoic (65 - 0 mya)
- Oligocene (38-24 mya)
a cooling period, creating savannahs - grazers and browsers radiate
Arsinotherium
IV. Cenozoic (65 - 0 mya)
- Oligocene (38-24 mya)
IV. Cenozoic (65 - 0 mya)
- Oligocene (38-24 mya)
a cooling period, creating savannahs - browsers radiate
Indricotherium (Baluchitherium)
IV. Cenozoic (65 - 0 mya)
- Oligocene (38-24 mya)
Titanotheres
IV. Cenozoic (65 - 0 mya)
- Miocene (24 - 5 mya) – “NEOGENE”
IV. Cenozoic (65 - 0 mya)
- Miocene (24-5 mya)
Extensification of grassland habitats
Radiation of grazer fauna: camelids, horse ancestors, cervids, rhinos
IV. Cenozoic (65 - 0 mya)
- Miocene (24 - 5 mya)
True Dog and Cat Carnivores replace creodonts
IV. Cenozoic (65 - 0 mya)
- Pliocene (5 - 2 mya)
IV. Cenozoic (65 - 0 mya)
- Pliocene (5 - 2 mya)
Sloths, Armadillos, Porcupines, Opposum
Deer, horses, monkeys, cats and dogs, rodents
Great American Interfaunal Exchange
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
American Mastodon Mammut americanum
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
Complete Mitochondrial Genome and Phylogeny of Pleistocene Mammoth Mammuthus primigeniusEvgeny I. Rogaev, et al. 2006. PLoS.
Hyrax
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K) - Periodic Ice Ages
391.06 (2010)
379.1 (2005)
Last Maximum ~ 18,000 ybp
IV. Cenozoic (65 - 0 mya)
- Pleistocene (2 mya - 10K)
Extinction of the Pleistocene Megafuana
- Human overhunting and keystone effects
- Climate change
- diseases brought by humans and their dogs.