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Why did some mammals develop tusks?（图）
二齿兽 哺乳动物 脊椎动物
2023/6/21
Awide array of animals have tusks, including elephants, walruses, warthogs, hippos, and even the much smaller hyrax, which look like guinea pigs and are about the size of domestic cats. The other thin...
Fossils support new hypothesis for origin of hoofed mammals（图）
Fossils support new hypothesis origin hoofed mammals
2020/12/11
New research published in the Journal of Vertebrate Paleontology describes a fossil family that illuminates the origin of perissodactyls -- the group of mammals that includes horses, rhinos ...
Six million years ago, atmospheric shifts led to increased diversity of grassland mammals（图）
Six million years ago atmospheric shifts grassland mammals
2019/10/30
Six million years ago, grass-eating mammals became more diverse in South America. Shifts in tropical atmospheric circulation known as Hadley circulation led to changes in climate and vegetation, espec...
Changes in conservation planning can benefit vulnerable mammals
Changes conservation planning vulnerable mammals
2017/7/24
Right now, a prairie dog in Colorado is busy increasing soil carbon retention, increasing water infiltration, and clipping vegetation that will help maintain local grasslands and provide nut...
Infectious disease transmission in fish,mammals,other animals has implications for humans
Infectious disease transmission fish mammals other animals implications for humans
2017/4/27
Scientists once thought that being part of a community would protect animal populations from infectious disease outbreaks, but now they've learned otherwise, according to a study published this week i...
Changing Views of Evolutionary Factors at Work on Earliest Mammals
Changing Views Evolutionary Factors Earliest Mammals
2016/11/29
Using 3D-printed replicas of 200-million-year-old mammal teeth and polymers that mimic insect prey, scientists at the University of Massachusetts Amherst this week provide the first laboratory-tested ...
Protein Evolution in Different Cellular Environments: Cytochrome b in Sharks and Mammals’
Cellular Environment Sharks and Mammals’
2015/12/17
DNA sequences for the mitochondrial cytochrome b gene were determined for 13
species of sharks. Rates and patterns of amino acid replacement are compared for
sharks and mammals. Absolute rates of ...
The Secret Life of Marine Mammals: Novel Tools for Studying Their Behavior and Biology at Sea
Marine Mammals Behavior and Biology
2015/8/19
Given the interest by both the lay and scientific communities, it is surprising how little is known about the open ocean ecology of marine mammals. Their patchy distribution and low abundance leads to...
Marine Mammals as Sentinel Species for Oceans and Human Health
Marine Mammals Sentinel Species Oceans and Human Health
2015/7/23
As more humans inhabit coastal regions, a global "anxiety" is developing about the health of our aquatic ecosystems. This anxiety is particularly prevalent in the United States, where more than half t...
Over the last 50 years, international public concern regarding human impact on the environment has increased drastically. Specific to the maritime domain, attention has more acutely focused during the...
NEW MULTITUBERCULATE MAMMALS FROM THE LOWER CRETACEOUS (SHAHAI AND FUXIN FORMATIONS), NORTHEASTERN CHINA
LOWER CRETACEOUS MULTITUBERCULATE
2014/3/26
Two eobaatarid multituberculates, Heishanobaatar triangulusgen. et sp. nov. and Eobaataridae gen. et sp.
indet., and an ?albionbaatarid multituberculate, Kielanobaatar badaohaoensis gen. et sp. nov.,...
The retroviruses which gave rise to HIV have been battling it out with mammal immune systems since mammals first evolved around 100 million years ago – about 85 million years earlier than previously t...
Carbon payments help protect threatened tropical mammals
Carbon payments threatened tropical mammals REDD
2009/6/8
The University of Queensland has found paying to preserve carbon stored in forests could protect endangered wildlife such as Indonesia's orangutans. Based on prices now being paid for carbon dioxide (...
《The Descent of Man, and Selection in Relation to Sex》Chapter XVIII Secondary Sexual Characters of Mammals, continued
The Descent of Man, and Selection in Relation to Sex 人类由来与性选择 查尔斯·达尔文 Charles Darwin
2008/12/22
QUADRUPEDS use their voices for various purposes, as a signal of
danger, as a call from one member of a troop to another, or from the
mother to her lost offspring, or from the latter for protectio...
《The Descent of Man, and Selection in Relation to Sex》Chapter XVII Secondary Sexual Characters of Mammals
The Descent of Man, and Selection in Relation to Sex 人类由来与性选择 查尔斯·达尔文 Charles Darwin
2008/12/22
WITH mammals the male appears to win the female much more through
the law of battle than through the display of his charms. The most
timid animals, not provided with any special weapons for fighti...