Early ancestors of primates and marsupials survived when asteroids attacked 66 million years ago and wiped out birds and dinosaurs unrelated to three-quarters of life on Earth, according to new research. It was one of the only tree-dwelling (arboreal) mammals. ..
Tree species were particularly endangered due to global deforestation caused by wildfires under the influence of asteroids.
In this study, computer models, fossil records, and information from living mammals revealed that most of the surviving mammals were tree-independent, but a few living, including human ancestors. Arboreal mammals may have been versatile enough to adapt to tree loss.
The study points to the impact of this extinction event, known as the Cretaceous-Paleogene (K-Pg) boundary, on shaping the early evolution and diversification of mammals.
“One of the possible explanations for how primates survived across the K-Pg boundary despite being arboreal may be due to their behavioral flexibility. Jeremy Saar’s The lead author of the laboratory, a doctoral student, and a professor of ecology and evolutionary biology in the Faculty of Agriculture and Life Sciences. Co-lead authors Jacob Berv, Ph.D. ’19 is currently a Life Sciences Fellow at the University of Michigan. ..
A study published in the journal on October 11 “Evolution of ecological selectivity and mammalian substrate preference across the K-Pg boundary” Ecology and evolution..
Early mammals emerged about 300 million years ago and may have diversified in parallel with the expansion of flowering plants about 20 million years before the K-Pg event. Many of these mammalian strains died when the asteroids collided, Hughes said.
“At the same time, the surviving mammals have diversified into all the new ecological niches that opened when dinosaurs and other species became extinct,” Hughes said.
In this study, researchers used published phylogeny for mammals (branching, tree-like diagrams showing evolutionary relationships between groups of organisms). Each of their phylogenetic living mammals was then categorized into three categories, arboreal, semi-arboreal, and non-arboreal, based on their preferred habitat. They also designed a computer model that reconstructs the evolutionary history of mammals.
Mammalian fossils around the K-Pg are extremely rare and difficult to use to interpret animal habitat preferences. Researchers have helped compare information known from living mammals with available fossils to provide additional context for the results.
In general, the model showed that the species that survived the K-Pg event were predominantly non-arboreal, with two possible exceptions: primates and marsupial ancestors. Primate ancestors and their close relatives were found to be arboreal shortly before the K-Pg event in all models. Marsupial ancestors were found to be arboreal in half of the model reconstructions.
The researchers also looked at how mammals as a group changed over time.
“We found that before and after the time frame leading up to the K-Pg event, there was a large spike in the transition from trees and semi-trees to non-trees, so most are not just non-trees. Tree [species]But things quickly moved away from the arboretum, “Hughes said.
Co-authors include Daniel Field, a vertebrate paleontologist at the University of Cambridge. Eric Sajisi, Professor of Anthropology at Yale University. Stephen Chester, an associate professor of anthropology at Brooklyn College.
This study was funded by the National Science Foundation.
Primate ancestors may have left trees to survive the asteroid-ScienceDaily
https://www.sciencedaily.com/releases/2021/10/211013114039.htm Primate ancestors may have left trees to survive the asteroid-ScienceDaily