Therians

[PB666]

http://phys.org/news/2016-06-mammals-began-takeover-death-dinosaurs.html

http://phys.org/news/2013-10-early-mammal-varieties-declined.html#nRlv

http://phys.org/news/2014-12-asteroid-dinosaurs-mammals.html#nRlv

Basically articles about the KT transition

 

[kerbiloid]

Dinos had extincted and left the mammals without dinoeggs and dinochickens.

That was dishonest, lovesome fuzzies began to starve.

[PB666]

10 minutes ago, kerbiloid said:

Dinos had extincted and left the mammals without dinoeggs and dinochickens.

That was dishonest, lovesome fuzzies began to starve.

That makes about a much sense as a screen door on a submarine.

[kerbiloid]

13 minutes ago, PB666 said:

That makes about a much sense as a screen door on a submarine.

If you were an ancient mammal, hiding from carnivorous dinos under the daylight and eating dinochickens sleeping in the cold of night, you would miss that tasty little dinos if they extinct.

[PB666]

Dino eggs would be hard to crack. I wonder how much having you biome cooked in a broiler for a day would affect your risk?

 

[PB666]

http://www.bbc.com/news/uk-england-hampshire-36471746

[Green Baron]

Well, the huge dinosaurs were products of a supercontinent that could support such massive organisms, their number declined with the narrowing of their niche when the large continent broke up. The impact just gave them them the rest, roughly 30-40% of landliving species died out. Hadrosaurus lived in france in the early palaeogene and one group of dinosaurs (saurischia) evolved into the birds, well, today are the birds. But it's very difficult to correlate the stratigraphy between america and europe. There are several models that try to explain the extinction event 66my ago.

It's not quite clear at what time the first mammals ran about (therapsides shed some light on that), but probably late triassic, first traces reaching until the upper permian (see: cynodontia evolution, but i don't know whether wikipedia is the right place to look that up ...). So, year, at the end of the cretacious there was probably a whole zoo of them, or, to put it less pejorative, they had their niches and that was more than eating dino eggs and hiding from big fearsome reptiles.

And they were most likely as effected from the KT-event as the reptiles.

If i was a small mammal from early cretacious i'd live at twilight ...

Edited June 8, 2016 by Green Baron

[PB666]

5 minutes ago, Green Baron said:

Well, the huge dinosaurs were products of a supercontinent that could support such massive organisms, their number declined with the narrowing of their niche when the large continent broke up. The impact just gave them them the rest, roughly 30-40% of landliving species died out. But Hadrosaurus lived in france in the early palaeogene. But it's very difficult to correlate the stratigraphy between america and europe. There are several models that try to explain the extinction event 66my ago.

It's not quite clear at what time the first mammals ran about (therapsides could shed some light on that), but probably late triassic, first traces reaching until the upper permian (see: cynodontia evolution, but i don't know whether wikipedia is the right place to look that up ...). So, year, at the end of the cretacious there was probably a whole zoo of them, or, to put it less pejorative, they had their niches and that was more than eating dino eggs and hiding from big fearsome reptiles.

And they were most likely as effected from the KT-event as the reptiles.

If i was a small mammal from early cretacious i'd live at twilight ...

True mammals Eutheria, before the KT event. Therians probably back to 165-180 million years ago and the Prototherian branch back to before 200-260 mya. There are no definitives on this, the branch had to be before 160 mya (the earliest known therian fossil) but there are no prototherian fossils from the Triassic or Jurassic periods. Its a void in the fossil record frequently found with isolated species. 

Eutherians probably lived in dense brush and understory of large forests, they seem to have an affinity for fruiting plants and flowering plants, they might have been excellent climbers that climbed trees and gathered fruits and berries, as with many mammals they may have kept caches of seeds, that aided them through the KT (CP) event.

Mammaliformes (somewhere around prototherian branch)

https://en.wikipedia.org/wiki/Morganucodonta

https://en.wikipedia.org/wiki/Adelobasileus

https://en.wikipedia.org/wiki/Allotheria

https://en.wikipedia.org/wiki/Castorocauda

At the Metatherian/Eutherian branch.

https://en.wikipedia.org/wiki/Juramaia

 

[DDE]

4 hours ago, Green Baron said:

Well, the huge dinosaurs were products of a supercontinent that could support such massive organisms, their number declined with the narrowing of their niche when the large continent broke up.

Wait, didn't the formation of the Pangea cause The Great Dying (tm) of the Perm-Triassian? By the golden age of the larger sauropods it had already fractured, hasn't it?

[Green Baron]

10 hours ago, DDE said:

Wait, didn't the formation of the Pangea cause The Great Dying (tm) of the Perm-Triassian? By the golden age of the larger sauropods it had already fractured, hasn't it?

You are right, i simplified terribly to avoid wall of text which i hate to read in a game forum. It is not sure what caused the extinction event at the end of the permian, probably a combination of factors. The forming of a continent isn't a sudden thing. And in the fossil records of a few million years look quite compressed.

There are other factors, climate and geographic conditions. In the >200my there was one ice age as well as a huge desert, both limiting life bearing capacity. Let me suggest a decent book on vertebrate evolution, like f.e. Benton: Vertebrate evolution (2014). It's a dry matter but compresses most knowledge in a readable format and tells when there are diverging views between scientists. I distrust Wikipedia greatly on all things evolution.

 

Edited June 9, 2016 by Green Baron

[kerbiloid]

18 hours ago, PB666 said:

Dino eggs would be hard to crack.

Most of dinos were not whale-sized. Only the biggest eggs were 2 ft long.
Really big dinos had an inertial homeothermy and could be active in the night, but they were much, much larger than their eggs.
Small dinos were cold-blooded and slept all night till sunset, as any honest lizard.
Enough possibilities for a smart rat or ferret to have a nice dino dinner.

[DDE]

2 hours ago, Green Baron said:

You are right, i simplified terribly to avoid wall of text which i hate to read in a game forum. It is not sure what caused the extinction event at the end of the permian, probably a combination of factors. The forming of a continent isn't a sudden thing. And in the fossil records of a few million years look quite compressed.

It's KSP we're talking about, and this is the off-topic sub-forum. It's got nothing on the even more geeky threads.

The theory is that it was a combination of a massive homogenous landmass near the equator turning into one giant desert, and a boost to greenhouse effect due to a spike in volcanic activity associated with a lot of landmass crashing into each other.

[PB666]

3 hours ago, Green Baron said:

You are right, i simplified terribly to avoid wall of text which i hate to read in a game forum. It is not sure what caused the extinction event at the end of the permian, probably a combination of factors. The forming of a continent isn't a sudden thing. And in the fossil records of a few million years look quite compressed.

There are other factors, climate and geographic conditions. In the >200my there was one ice age as well as a huge desert, both limiting life bearing capacity. Let me suggest a decent book on vertebrate evolution, like f.e. Benton: Vertebrate evolution (2014). It's a dry matter but compresses most knowledge in a readable format and tells when there are diverging views between scientists. I distrust Wikipedia greatly on all things evolution.

 

Since when is a wall of words two very short paragraphs. This geberation has an attention span of a 2week old tree schrew. 

[Green Baron]

33 minutes ago, PB666 said:

Since when is a wall of words two very short paragraphs. This geberation has an attention span of a 2week old tree schrew. 

 

Hi,

an elaboration could fill pages, that's why. DDE wrote a summary. Flood basalt, global icing, an equatorial desert, gas release after icing, an already stressed environment (well, it's always stressed out, isn't it :-) ?) ... could have played a role in the extinction event at the end of the permian. A long and warm period with epicontinental seas, global subtropic/tropic conditions (someone get me a gintonic), huge connected landmasses were the world of the dinosaurs.

E.g.: elephants will not multiply on an island and maintain their size, an island would not be able to support enough individuals to keep the gene pool intact. They would either die out or get much smaller (like the last mammoth populations on siberian islands). I'm probably telling you a common place here, sorry if i do.

I saw a misunderstanding in my post: you as the op were talking about already specialized mammals at the end of the cretacious, and i came up with the base of mammal evolution. I think we all agree that mammals, though not the dominant families of species, had a varied family tree and filled many niches at the end of the cretacious. And were better able to adapt to the new, gradually cooling and much more climatically diverse world than the saurians, the latter spreading rapidly into the air.

 

Pls. excuse me, i don't get your second sentence ... 

 

 

[wumpus]

On 6/8/2016 at 9:35 AM, kerbiloid said:

Dinos had extincted and left the mammals without dinoeggs and dinochickens.

That was dishonest, lovesome fuzzies began to starve.

To be honest, I suspect that the surviving [what would become birds] population could very easily be called dinochickens and had eggs that mammals could eat.  Well at least the surviving mammals.  It would be shocking if there wasn't a huge loss in mammalian species in such a dramatic event as the loss of the dinosaurs.

[jwenting]

On ‎6‎/‎8‎/‎2016 at 5:05 PM, PB666 said:

Dino eggs would be hard to crack. I wonder how much having you biome cooked in a broiler for a day would affect your risk?

 

Not only were most dinosaurs small creatures, given their close relation to reptiles it's quite likely they had soft shell eggs like reptiles (though later species might have had hard shell eggs like birds).

As said, it was highly insensitive for the dinosaurs to die and leave egg eating mammals without a supply of food.

[kerbiloid]

3 hours ago, wumpus said:

To be honest, I suspect that the surviving [what would become birds] population could very easily be called dinochickens and had eggs that mammals could eat.  Well at least the surviving mammals.  It would be shocking if there wasn't a huge loss in mammalian species in such a dramatic event as the loss of the dinosaurs.

Of course, dinoeggs and dinochickens were not the main problem of the mammals, I'm slightly overdrawing.
(Though, the birds didn't dominate while reptiles ruled the world, eating any other creatures enough large to be seen. Epoch of giant birds domination began a bit later. So, most chicken and eggs seem to be dinos'.)

The author which I respect (Kirill Eskov), tells the following.
The first plants were gymnospermous. There was no true grass form of them, their buttons were poorly edible.
The first mammals (we too) and reptiles were entomophagous, eating insects populating that dull green inedible bush,

As reptiles have more primitive body (no thermal regulation, primitive limbo joints, thight skin), they had short-term evolutionary advantages.
So, they had grown up first and occupied the world.
As they were enough large, they could eat and digest poor inedble ferns - just as a cows does. A small animal quickly loses energy and cannot wait while its inner bacteria digest the cellulose, it needs more caloric food.
As they were too large, they needed and could eating large animals, not only insects.
So, once a mammal appeared to be bigger than a rat, it became a lunch for a dino.

Then flowering plants spread around. They produced much more fleshy and caloric buttons, which became an important food for all small critters, including the mammals.
Some of them appeared to be neotenic form — grass, and those spread especially wide and fast, almost at any place where something can grow at all.
A grass lives fast, dies young. Its button (and thus, seeds) makes a large part of the whole plant. So, when grass covered any empty place, small critters got a demographic burst thanks to such huge amount of food.

Once small herbivorous mammals ("rats") spread around, there quickly appeared small carnivorous mammals ("ferrets"), eating any creature enough small to be eaten: no matter, a mammal, an insect, a bird, or a reptile.
As mammals are homothermal beings, they hunted in the night when lizards and small dinos get cold and sleep, while big dinos just don't notice those miserable hoppers.
As a result, they have successfully eaten small reptiles and dominated in a small size class.

So, they weren';t a direct danger for big dinos, but even the largest dinos have small eggs and small chickens - as a chicken by size and taste.
Thus, big dinos couldn't protect their eggs and youngsters against this plague, and small mammals were a nightmare of their future. Little dinos were thrown into a dungeon with rats. Literally.

As dinos were too large to evolve fast, and their babies were being extinguished by "rats" and "ferrets", their condition became very unstable and strongly depended on any bad news.
They began to extinct and did this for millions years before the asteroid became the last drop which overbrimmed their cup.

Once this happens many mammals die, but they quickly respawned as every small annoying trouble.
While dinos appeared not to be enough numerous and fast-growing.

Once the dinos disappear, there was an epoch when giant birds tried to take their place and dominate over smaller animals.
But mammals were already enough smart and advanced, they have eaten the giant birds too (the last of them - about two centuries ago).

Edited June 10, 2016 by kerbiloid

[PB666]

5 hours ago, jwenting said:

Not only were most dinosaurs small creatures, given their close relation to reptiles it's quite likely they had soft shell eggs like reptiles (though later species might have had hard shell eggs like birds).

As said, it was highly insensitive for the dinosaurs to die and leave egg eating mammals without a supply of food.

By definition dino saur means giant lizard. 

[jwenting]

17 hours ago, PB666 said:

By definition dino saur means giant lizard. 

The name was given to the entire line when only a few giant skeletons had been found, and it stuck. When later small species were also discovered, and it was found that they evolved into birds over the millions of years, it was too late to change.
 

[PB666]

9 hours ago, jwenting said:

The name was given to the entire line when only a few giant skeletons had been found, and it stuck. When later small species were also discovered, and it was found that they evolved into birds over the millions of years, it was too late to change.
 

And so they are called therapods. Interesting isn't it. Dinosaurs are a subset of therapods. Edit, I should say some Dinosaurs are theropods, obviously there are some non-saurichian dinosaurs. Ornithischia. As the wiki article on dinosaurs explains using the word "Avian dinosaur" creates unnecessary confusion.

thera - beast

pod - feet

There are large therapod megafauna (dinosaurs) and just plain fauna. Maniraptora (extant),  Alvarezsauroidea (extinct)

Edited June 11, 2016 by PB666