The Earth has been through a lot of changes in its 4.5 billion year history, including a shift to incorporating and retaining volatile compounds such as water, nitrogen and carbon from the atmosphere in the mantle before spewing them out again through volcanic eruptions.
This transport could not have begun much before 2.5 billion years ago, according to researchers at UC Davis and Washington University in St. Louis, published Aug. 9 in the journal Nature.
Telomeres are repetitive nucleotide sequences that act as protective “caps” at the end of DNA strands. As cells age, either as a function of time or as a result of stress and poor health, telomeres tend to shorten. As such, telomere lengthcan be used as a crude biological marker of health and well-being.
Telomeres are caps at the end of a chromosome. They become shorter with aging. (Getty Images)
A recent study by researchers at the University of California Davis, Center for Mind and Brain, measured changes in telomere length, telomerase (the enzyme which replenishes telomeres), and telomere-regulating genes in a group of individuals who participated in a month-long Insight meditation retreat.
A gene implicated in affecting speech and language, FOXP2, is held up as a “textbook” example of positive selection on a human-specific trait. But in a paper in the journal Cell on Aug. 2, researchers challenge this finding. Their analysis of genetic data from a diverse sample of modern people and Neanderthals saw no evidence for recent, human-specific selection of FOXP2 and revises the history of how we think humans acquired language.
What makes us human? The FOXP2 gene has been associated with uniquely human language abilities. But a new study with a wider variety of people shows no evidence of selection for FOXP2 in modern humans. (Image by Brenna Henn, UC Davis)
Doctoral candidate Philipp Brand and his colleagues at the University of California, Davis, had just finished compiling the genome, or complete set of genetic material of the firebrat — a tiny wingless, nocturnal insect found throughout much of the world — when something surprised him.
Adult firebrat (left) and developmental stages. Firebrats are among the most ancient types of insects and can be pests attacking paper and fabrics. Photo by Dong-Hwan Choe, UC IPM.
There they were–odorant receptor genes, the scent-detecting genes thought to have evolved with winged insects more than 400 million years ago. But this groundbreaking discovery indicates they evolved millions of years earlier.
How does a fish avoid being eaten by a bigger fish? Evolution could build up defenses such as spines or armor, or favor avoidance strategies such as quick reactions, swimming away and hiding. The rules of evolution are tough, so you cannot really have both, the argument goes.
But this hypothesis has been difficult to test in practice. Now Jennifer Hodge, a postdoctoral researcher working with Professor Peter Wainwright and colleagues in the UC Davis Department of Evolution and Ecology, College of Biological Sciences, has carried out a survey of hundreds of specimens of butterflyfish, carefully measuring their physical traits and defenses compared to feeding style.
As lizards before the hurricane fly: A new study in the journal Nature gives a graphic demonstration of natural selection in action. It’s about Anole lizards living on islands in the Caribbean and how they survived – or not – two violent hurricanes in 2017.
Anolis scriptus lizards are endemic to the Turks and Caicos Islands. (Colin Donihue/Harvard University)
Thomas Schoener, professor of evolution and ecology in the UC Davis College of Biological Sciences, is a coauthor on the paper. Schoener has extensively studied these lizards and other animals on small Caribbean islands as models for evolution and natural selection.
Watch a movie backwards and you’ll likely get confused – but a quantum computer wouldn’t.
In research published 18 July in Physical Review X, an international team shows that a quantum computer is less in thrall to the arrow of time than a classical computer. In some cases, it’s as if the quantum computer doesn’t need to distinguish between cause and effect at all.
We find it easier to understand events in time sequence, but a quantum computer may not be so limited, say researchers at UC Davis and the National University of Singapore. Image by Aki Honda/Centre for Quantum Technologies, National University of Singapore.
The snipefish, an ocean-dwelling relative of the seahorse, has a very long, skinny snout ending in a tiny mouth. A recent study by UC Davis graduate student Sarah Longo shows that snipefish feed with an elastic-boosted head flick at almost unprecedented speed.
“At as little as two milliseconds, it’s among the fastest feeding events ever recorded for fish,” said Longo, now a postdoctoral researcher at Duke University.
Snipefish, seahorses and pipefish all have long, skinny snouts and use “pivot feeding” to capture food, Longo said, meaning that they pivot their head rapidly to bring their mouth up close to the prey and suck it in.
Josh Hihath is trying to fuse biology and electrical engineering and to build new types of electronic memory based on DNA. Hihath, professor in the UC Davis Department of Electrical and Computer Engineering, is principal investigator of a grant just funded by the Semiconductor Synthetic Biology for Information Processing and Storage Technologies (SemiSynBio) program. SemiSynBio is a partnership between the National Science Foundation and the Semiconductor Research Corporation.
Researchers at UC Davis, University of Washington and Emory University hope to use self-assembling DNA molecules to build a “DNA-ROM” that can store digital information. (Josh Hihath/Yonggang Ke)