Scientists know from previous studies that flying birds and bats live longer than earthbound animals of the same size. Milena Shattuck and Scott Williams, doctoral candidates in anthropology, decided to take a closer look at the relationship between habitat and lifespan in mammals, comparing terrestrial and treetop life. They published their findings in the Proceedings of the National Academy of Sciences.
The two hypothesized that, like flight, treetop or arboreal dwelling reduces a species’ extrinsic mortality – death from predation, disease and environmental hazards; that is, causes other than age.
“One of the predictions of the evolutionary theory of aging is that if you can reduce sources of extrinsic mortality, you’ll end up exposing some of the late-acting mutations to natural selection, and therefore evolve longer lifespans,” Williams said.
Williams and Shattuck found that for arboreality, the theory holds. Mammals who spend the majority of their time up a tree enjoy longevity over those who scurry along the ground. The pattern holds consistent both on the large scale among all mammals, and also in specific classes the pair studied, such as tree squirrels versus ground squirrels.
However, the pair also uncovered two classes of mammals that buck the longevity trend – marsupials, such as kangaroos, and primates, including ground walkers such as gorillas and humans and their branch-swinging counterparts. Aloft or not, these groups show no significant difference, although primates in general tend to lead long lives.
“These are the exceptions that prove the rule,” Shattuck said. “The defining feature that seems to connect those two groups is a long history of arboreal ancestors. Other mammals started out terrestrially, and separate groups developed arboreality independently. Marsupials and primates seem to have started off in the trees, and then the terrestrial marsupials and primates have descended from arboreal ancestors.”
This arboreal ancestry may partially explain why humans have such a long lifespan relative to other mammals. As primates descended from the trees, they had to develop new strategies for survival on the ground. Terrestrial primates, including humans, tend to be larger and more social, providing some security from predators and environmental obstacles.
“It’s interesting to think that humans, at least in part, live so long and do well because we had this evolutionary history when we were in the trees,” said Shattuck. “And now, we have the intervention of culture and medicine to help extend that further.”
This work was sponsored by a Cognitive Science/Artifical Intelligence Grant from the U. of I.’s Beckman Institute for Advanced Science and Technology.
Liz Ahlberg | University of Illinois
New quantum phenomena in graphene superlattices
19.09.2017 | Graphene Flagship
Solar wind impacts on giant 'space hurricanes' may affect satellite safety
19.09.2017 | Embry-Riddle Aeronautical University
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...
Scientists from the MPI for Chemical Energy Conversion report in the first issue of the new journal JOULE.
Cell Press has just released the first issue of Joule, a new journal dedicated to sustainable energy research. In this issue James Birrell, Olaf Rüdiger,...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
19.09.2017 | Event News
19.09.2017 | Physics and Astronomy
19.09.2017 | Power and Electrical Engineering