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This was a giant mammal that coexisted with dinosaurs. I had always thought that mammals appeared during the age of dinosaurs, but they were all tiny mouse-siz

This was a giant mammal that coexisted with dinosaurs. I had always thought that mammals appeared during the age of dinosaurs, but they were all tiny mouse-sized mammals.

gus_massa 8y ago
They were not mammals. They were more related to the ancestors of mammals than to the dinosaurs. The article calls them "mammal-like reptiles". You can see in this graph when their ancestors an our ancestor split. https://en.wikipedia.org/wiki/Evolution_of_mammals#Therapsid_family_tree https://en.wikipedia.org/wiki/Evolution_of_mammals#Therapsid... It's the third branching in this graph. For comparison, see the graph in the same page https://en.wikipedia.org/wiki/Evolution_of_mammals#The_ancestry_of_mammals https://en.wikipedia.org/wiki/Evolution_of_mammals#The_ances... . Here is the split between reptiles/dinosaurs/birds and the ancestors of mammals in the second branching. (You can "glue" the other graphic in the lowest branch of this graphic, but I'm not sure if they have a comparable level of detail.)
Scriptor 8y ago
Not quite mammals but mammal-like reptiles. They're related to mammals but not our direct ancestors, more like aunts and uncles in the evolutionary family tree.
gnulinux 8y ago
Imagine the latest common ancestor of all mammals i.e. the last individual that all mammals are related to. The species in the article would not be an N-th degree child of this individual, but it would be an N-th degree cousin of this individual.
Arnt 8y ago
The ones that survived the Giant Frying were mouse-sized, but bigger ones existed before then, even though they might look mouse-sized to a passing brontosaurus. (On the Giant Frying: http://uahost.uantwerpen.be/funmorph/raoul/macroevolutie/robertson2004.pdf http://uahost.uantwerpen.be/funmorph/raoul/macroevolutie/rob... )
- nerdponx 8y ago
  There's nothing quite like a well-written scientific paper. This isn't my field at all but I enjoyed reading this immensely.
bunderbunder 8y ago
Well, the article keeps saying "mammal relatives". They're really just saying it was a cynodont. Mammals are the only remaining cynodonts, but there used to be other kinds. I'm pretty sure this doesn't challenge the idea that, at the time, mammals were all still small shrew-like jobbies. For one (totally not a biologist, but I do spend way too much time at museums) its skull doesn't really look mammalian to me.

This was a giant mammal that coexisted with dinosaurs. I had always thought that mammals appeared during the age of dinosaurs, but they were all tiny mouse-sized mammals.

gus_massa 8y ago

They were not mammals. They were more related to the ancestors of mammals than to the dinosaurs. The article calls them "mammal-like reptiles". You can see in this graph when their ancestors an our ancestor split. https://en.wikipedia.org/wiki/Evolution_of_mammals#Therapsid_family_tree https://en.wikipedia.org/wiki/Evolution_of_mammals#Therapsid... It's the third branching in this graph. For comparison, see the graph in the same page https://en.wikipedia.org/wiki/Evolution_of_mammals#The_ancestry_of_mammals https://en.wikipedia.org/wiki/Evolution_of_mammals#The_ances... . Here is the split between reptiles/dinosaurs/birds and the ancestors of mammals in the second branching. (You can "glue" the other graphic in the lowest branch of this graphic, but I'm not sure if they have a comparable level of detail.)

Scriptor 8y ago

Not quite mammals but mammal-like reptiles. They're related to mammals but not our direct ancestors, more like aunts and uncles in the evolutionary family tree.

gnulinux 8y ago

Imagine the latest common ancestor of all mammals i.e. the last individual that all mammals are related to. The species in the article would not be an N-th degree child of this individual, but it would be an N-th degree cousin of this individual.

Arnt 8y ago

The ones that survived the Giant Frying were mouse-sized, but bigger ones existed before then, even though they might look mouse-sized to a passing brontosaurus. (On the Giant Frying: http://uahost.uantwerpen.be/funmorph/raoul/macroevolutie/robertson2004.pdf http://uahost.uantwerpen.be/funmorph/raoul/macroevolutie/rob... )

nerdponx 8y ago
There's nothing quite like a well-written scientific paper. This isn't my field at all but I enjoyed reading this immensely.

bunderbunder 8y ago

Well, the article keeps saying "mammal relatives". They're really just saying it was a cynodont. Mammals are the only remaining cynodonts, but there used to be other kinds. I'm pretty sure this doesn't challenge the idea that, at the time, mammals were all still small shrew-like jobbies. For one (totally not a biologist, but I do spend way too much time at museums) its skull doesn't really look mammalian to me.