Taxonomy term

evolution

Bat signals

Bats, the only true-flight mammals, first appeared during the Early Eocene after a period of acute global warming known as the Paleocene-Eocene Thermal Maximum. Despite decades of study, however, much remains unknown about bats. Recent discoveries are shedding new light on the natural history of these creatures, which today comprise one of the most diverse mammalian groups.

07 Apr 2016

Parasites of the Paleozoic

Parasitism — an ecological relationship in which one species benefits at the expense of its host — is common among living organisms, but as most parasites are soft-bodied, it’s rare to find them preserved in the fossil record. Two recent discoveries, however, have lengthened the short list of ancient parasites

03 Mar 2016

Ancient eggshells may reveal dinosaur body temperatures

Whether dinosaurs had metabolisms more like slow, cold-blooded reptilians or fast, warm-blooded birds has long been a mystery. Fossilized bones, which don’t preserve the delicate cell membranes that facilitate heat production in warm-blooded animals, are not likely to answer the question. Fossilized eggshells, however, might be just the ticket to determining the past body temperatures of egg-laying females, which, scientists say, might help address whether the dinosaurs’ metabolisms were warm or cold.
 
27 Jan 2016

Land plants came prepared for terrestrial life

Plants colonized land between 450 million and 420 million years ago, and, once there, they drastically altered terrestrial landscapes and provided resources for animals leaving the oceans around the same time. One adaptation that helped plants gain a foothold on land is a symbiosis with fungi known as arbuscular mycorrhizae (AM), which help plants acquire water and key nutrients from the soil and are still associated with most land plants today. In return, plants provide the fungi with bioavailable carbon produced during photosynthesis. When this symbiosis evolved has remained unclear, but researchers recently discovered that it likely has roots in a group of freshwater algae ancestral to land plants.
 
22 Jan 2016

Three new species of extinct baleen whales found

The evolution of baleen whales from toothed whales was gradual, with intermediate fossil species found that possess both teeth and baleen. Now, the discovery of three new whale species on New Zealand’s South Island is filling in the evolutionary story of baleen whales.
 
21 Jan 2016

Moroccan fossil formation reshapes timeline of Early Phanerozoic evolution

Many new life-forms emerged during both the Cambrian Explosion and the Great Ordovician Biodiversification Event, but a lack of fossils from the 40-million-year span in between has left scientists wondering if a period of evolutionary stasis took hold between the two booms. Now, the discovery of a prodigious bed of fossils in Morocco that date to between 485 million and 444 million years ago indicates that the Ordovician boom may actually have been a continuation of the Cambrian Explosion, with little to no evolutionary downtime in between.
02 Dec 2015

Oldest birds unearthed in China

The discovery of two well-preserved fossils in the Sichakou Basin of northeastern China has pushed back the known evolutionary record of birds by as much as 6 million years, according to a new study published in Nature Communications.
 
24 Aug 2015

De-evolving the bird beak

The transition from dinosaurs with snouts to birds with beaks was a pivotal change in the evolution of dinosaurs into birds during the Late Mesozoic. Now, biologists have partially reversed this process by transforming chicken embryos into specimens with snout and palate configurations similar to those of small dinosaurs like Velociraptor and Archaeopteryx.
 
21 Aug 2015

Geomedia: Books: To Tiktaalik and beyond

In 2008, Neil Shubin penned the terrific, “Your Inner Fish: A Journey into the 3.5-Billion-Year History of the Human Body,” in which he explored the stories of deep time as they are written in the details of our bodily architecture. As both a professor of anatomy and the paleontologist who discovered Tiktaalik, a transitional fossil between fish and amphibians, Shubin was ideally positioned to tell this tale.

 
18 Feb 2015

Geomedia: Books: Are we causing a sixth extinction?

Last year, Elizabeth Kolbert released her latest excellent book. Her previous volume, “Field Notes from a Catastrophe,” set a high bar for accessible, accurate science writing about environmental issues, but in my opinion, “The Sixth Extinction” surpasses it in several regards. Readers of this magazine will appreciate its solid geologic grounding and perspective, with entire chapters devoted to the end-Ordovician and end-Cretaceous extinctions, as well as sections on the principles of evolution and Earth history. Climate change, the focus of her earlier book, looms large here too, though it is just one of the many threats to the survival of our biosphere that Kolbert covers.

20 Dec 2014

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