This 2016 video says about itself:
Top 7 Prehistoric Mesozoic Mammals
Mesozoic Mammals. The first mammals on Earth. They lived among the giant dinosaurs (Mesozoic) but prevailed and evolved to control the planet and are our ancestors! Juramaia, the Jurassic mother, Repenomamus, the mammal that ate dinosaurs and much more!
From University College London in England:
Mammals switched to daytime activity after dinosaur extinction
November 6, 2017
Mammals only started being active in the daytime after non-avian dinosaurs were wiped out about 66 million years ago (mya), finds a new study led by UCL and Tel Aviv University‘s Steinhardt Museum of Natural History.
A long-standing theory holds that the common ancestor to all mammals was nocturnal, but the new discovery reveals when mammals started living in the daytime for the first time. It also provides insight into which species changed behaviour first.
The study, published today in Nature Ecology & Evolution, analysed data of 2415 species of mammals alive today using computer algorithms to reconstruct the likely activity patterns of their ancient ancestors who lived millions of years ago.
Two different mammalian family trees portraying alternative timelines for the evolution of mammals were used in the analysis. The results from both show that mammals switched to daytime activity shortly after the dinosaurs had disappeared. This change did not happen in an instant — it involved an intermediate stage of mixed day and night activity over millions of years, which coincided with the events that decimated the dinosaurs.
“We were very surprised to find such close correlation between the disappearance of dinosaurs and the beginning of daytime activity in mammals, but we found the same result unanimously using several alternative analyses,” explained lead author, PhD student Roi Maor (Tel Aviv University and UCL).
The team found that the ancestors of simian primates — such as gorillas, gibbons and tamarins — were among the first to give up nocturnal activity altogether. However, the two evolutionary timelines varied, giving a window between 52-33 mya for this to have occurred.
This discovery fits well with the fact that simian primates are the only mammals that have evolved adaptations to seeing well in daylight. The visual acuity and colour perception of simians is comparable to those of diurnal reptiles and birds — groups that never left the daytime niche.
“It’s very difficult to relate behaviour changes in mammals that lived so long ago to ecological conditions at the time, so we can’t say that the dinosaurs dying out caused mammals to start being active in the daytime. However, we see a clear correlation in our findings,” added co-author Professor Kate Jones (UCL Genetics, Evolution & Environment).
“We analysed a lot of data on the behaviour and ancestry of living animals for two reasons — firstly, because the fossil record from that era is very limited and secondly, behaviour as a trait is very hard to infer from fossils,” explained co-author, Professor Tamar Dayan (Chair of The Steinhardt Museum of Natural History, Tel Aviv University).
“You have to observe a living mammal to see if it is active at night or in the day. Fossil evidence from mammals often suggest that they were nocturnal even if they were not. Many subsequent adaptations that allow us to live in daylight are in our soft tissues.”
The team say further research is needed to better populate the mammalian family tree to give more accurate information on when the behaviour of species changes from night time to day time activity.
Sixty-five million years ago, clouds of ash choked the skies over Earth. Dinosaurs, along with about half of all the species on Earth, staggered and died. But in the seas, a colorful population of marine bivalves — the group including oysters, clams and scallops — soldiered on, tucked into the crevices of ocean floors and shorelines. Though they also lost half their species, curiously, at least one species in each ecological niche survived: here.
LikeLiked by 1 person
Wow. Amazingly huge!
LikeLike
They only became that big after the extinction of dinosaurs.
LikeLiked by 1 person
I see how that works
LikeLike
There were a lot more animals in the Mesozoic Era besides dinosaurs than I expected!
LikeLike
Yes, there were already the first birds. And lizards, snakes, crocodiles, turtles, other (now extinct) reptiles, fish, and of course insects and other invertebrates.
LikeLiked by 1 person
However, many of those animals are in the world today. Only, luckily dinosaurs are extinct at least
LikeLike
Arguably, there are still dinosaurs now, as birds are descendants of dinosaurs.
LikeLiked by 1 person
True
LikeLike
Pingback: Dinosaur age mammalian human ancestors discovery in England | Dear Kitty. Some blog
LikeLike
Pingback: Bad French mammal news | Dear Kitty. Some blog
Pingback: Human-sized fossil penguin discovery | Dear Kitty. Some blog
Pingback: African sea turtle’s dinosaur age journey to Europe | Dear Kitty. Some blog
Pingback: Dinosaur discovery in Egypt | Dear Kitty. Some blog
Pingback: Cretaceous dinosaur, mammal discovery in Maryland, USA | Dear Kitty. Some blog
Pingback: What makes dinosaurs dinosaurs? | Dear Kitty. Some blog
Pingback: Baby bird from dinosaur age discovered | Dear Kitty. Some blog
Pingback: Hispaniolan solenodon DNA sequenced | Dear Kitty. Some blog
Pingback: Strange fossil mammal discovery | Dear Kitty. Some blog
Pingback: Triassic dinosaurs’ explosion, new study | Dear Kitty. Some blog
Pingback: Octopus ancestry video | Dear Kitty. Some blog
Pingback: Life after dinosaur extinction | Dear Kitty. Some blog
Pingback: Cretaceous reptile-like mammal discovery in Utah, USA | Dear Kitty. Some blog
Pingback: Brazil’s oldest mammal named after David Bowie | Dear Kitty. Some blog
Pingback: Dinosaurs became extinct, sharks survived | Dear Kitty. Some blog
Pingback: Dinosaurs, gradual decline or sudden extinction? | Dear Kitty. Some blog
Pingback: From mammal-like reptiles to mammals | Dear Kitty. Some blog
Pingback: Why mammal ancestors became nocturnal | Dear Kitty. Some blog
Pingback: Repenomamus, dinosaur-eating mammals | Dear Kitty. Some blog