This is more fun. We have the idea that mammals were like noctural rats, cowering in fear until the dinosaurs went away. Maybe not: http://www.sciencedaily.com/releases/2015/07/150716123846.htm The article speaks highly also of the Cambrian explosion. It was no small thing, but please bear in mind that this was just in the ocean. Critters on land were much delayed until trees on land got their sh*t together and made food.
Imagine there were a 'war of survival' between flora and fauna say 66 million years ago. Only the dominant fauna was sensitive to cold. If flora evolved to survive a cold spell, they would have an advantage. Returning in the spring, flora might turn down the earth temperature by removal of greenhouse gasses. The resulting temperate climate would give them a survival advantage over fauna that needed that heat. Then fauna developed body-heat, fur and feathers, still not so bad, until one species figured out how to return CO{2} to the atmosphere. So today we see tropical fauna migrating to what had been too cold climates. Friday night, the dogs and I saw a suicidal armadillo crossing the road and a young possum. Both critters continue to move towards what had been colder climates in the recent past. Bob Wilson
The mammals may have still been cowering in fear while undergoing this evolutionary explosion. What the public sees as warm-bloodedness isn't as large of an advantage in warmer climes like existed during that period; see Komodo dragon. They weren't actually cowering, it is just that the traits that give mammals an edge over reptiles today, would really only be a real advantage during the night with the dinosaurs around. With this explosion, the mammals still stayed relatively small, but active warm-bloodedness would give them an advantage over the more cold-blooded reptiles of the time when the sun had set. The first mammals (in Kemp's sense) appeared in the Late Triassic epoch (about 225 million years ago), 40 million years after the first therapsids. They expanded out of their nocturnal insectivore niche from the mid-Jurassic onwards; Castorocauda, for example, had adaptations for swimming, digging and catching fish.[23] Most, if not all, are thought to have remained nocturnal (the Nocturnal bottleneck), accounting for much of the typical mammalian traits." - Mammal - Wikipedia, the free encyclopedia There were early mammals before the dinosaurs. The Therapsid - Wikipedia, the free encyclopedia were the dominate land animals back then, and possessed the traits that are seen as mammalian today; their limbs were under them for an upright gait instead to the sides like a lizard, the teeth are diversified into incisors, canines, and molars, and some may have possessed hair. An extinction event wiped out the majority of them, and gave the dinosaur's ancestors a chance.
So they were up all night because they were party animals, trying out the latest wild and crazy anatomies (17 feet tall? Communicates in ultrasonic? groovy ossicones? where can I get me some !!?? ) , not 'cause they were nervous? Cool.
I have some adult friends (Husband and Wife) that spend way too much time playing Minecraft. What's interesting is without my playing or having much involvement in the game at all, I've seen their evolution within the game. Every time I visit they would inevitably want to show me how far they had progressed in the game. (Yeah, my friends are nerds...but that's kind of cool). It's kind of interesting to me, because it is a simplified "cyber" evolution. And one of the first things you learn to do, at the earliest stages of the game is go shake tree's to make materials fall that you can benefit from.
