Sentences with phrase «as modern mammals»

«With each new discovery it becomes increasingly clear that the [earliest] mammals had the same evolutionary mechanisms as modern mammals,» he says.

Not exact matches

«In particular, we found a group called Laurasiatheria quickly increased their body size and ecological diversity, setting them on a path that would result in a modern group containing mammals as diverse as bats, cats, rhinos, whales, cows, pangolins, shrews and hedgehogs.»

If the extinction trend continues apace, modern elephants, rhinos, giraffes, hippos, bison, tigers and many more large mammals will soon disappear as well, as the primary threats from humans have expanded from overhunting, poaching or other types of killing to include indirect processes such as habitat loss and fragmentation.

Now, a new analysis using the same sort of computer software that engineers employ to analyze bridges and aircraft parts suggests that Kolponomos may have collected its shelly prey in a unique way: They might have used their teeth and formidable neck muscles to clamp down on clams, mussels, and other mollusks and then wrench them directly off the rocks to which they were attached, the researchers report online today in the Proceedings of the Royal Society B. (Modern marine mammals that consume such prey either slurp them right out of the shell, as walruses do, or pry them from the rocks using their forelimbs and then eat them, as otters do.)

The principles of infectious disease are the same as they have always been, but modern conditions, including life in proximity to pets and mammal - filled woods, are exposing us to new pathogen reservoirs and new modes of transmitting disease.

Earth's climate was transitioning from greenhouse to icehouse, and the ancestors of modern reptiles and mammals (as well as the precursors of dinosaurs) had begun to emerge from earlier large amphibians.

In spite of their size, these big mammals were extremely vulnerable, as are modern elephants.

One hypothesis suggests that Neandertals were rigid in their dietary choice, targeting large herbivorous mammals, such as horse, bison and mammoths, while modern humans also exploited a wider diversity of dietary resources, including fish.

Now an analysis of thousands of anatomical features of modern and extinct mammals, as well as molecular sequences from living species, is helping them to do just that.

Several modern mammal groups such as rodents emerged after the dinosaur extinction, and the fossils show their first members were small.

Modern conservation efforts tend to center around large animals — such as tigers, elephants, and wolves — and top predators in peril, while Roopnarine and Angielczyk show that small amniotes (reptiles and ancient mammal relatives) were most vulnerable during the early phase of this long - ago period of extinction.

The authors suspect that the presence of big teeth in fossil sperm whales may suggest that they were feeding on large prey, perhaps marine mammals such as seals and other smaller whales as opposed to modern sperm whales, which feed primarily on squid, hardly using their teeth for chewing.

«At the same time as this eclectic mix of ancient and modern - type marine mammals was living together, the marine mammal fauna in the North Atlantic and Southern Ocean were already in the forms we find today.»

The team discovered that the genes responsible for the regulation of NRL became more refined in the placental mammals as the modern retina evolved and were lost in several non-mammalian groups.

As no other taxonomic group contains terrestrial animals in the size classes of the large modern mammals, the functional loss of large mammals can rarely be compensated, leading to permanent ecosystem changes [49].

In order to reinforce their results, the scientists compared their data with more than 200 bones from modern mammals, whose diet is known, as well as with fossil specimens from both carnivores and herbivores.

Similar to spurs found on modern egg - laying mammals, such as male platypuses, the spur is evidence that this fossil was most likely a male member of its species.

Applying these strictures to modern animals is fairly straightforward, since these two characteristics are restricted only to members of the clade Ruminantia, which is the subgroup of even - toed hoofed mammals that includes the cattle, goats, sheep, antelopes, deer, pronghorn, mouse deer, giraffe (Zivotofsky 2000) and okapi (a clade is a taxonomic group whose members share a common ancestry; in this case it does not have a formal associated Linnaean level, such as family or order).

Perhaps as early as 3.4 million years ago, the modern human ancestor Australopithecus afarensis was using stone tools to strip meat from the bones of large mammals.

«Conclusion: As physical activity expenditure has not declined over the same period that obesity rates have increased dramatically, and daily energy expenditure of modern man is in line with energy expenditure in wild mammals, it is unlikely that decreased expenditure has fuelled the obesity epidemic.»

The city boasts a modern skyline and churches dating from the 1500's; late night discotheques and inviting parks with lush, tropical vistas; living museums for marine mammals as well as World War II shrines.

But as a marine mammal, the bear is exposed to a huge range of pollutants delivered by modern industry, transport and commerce.