Study Challenges Evolution of How Humans Acquired Language

By Karen Nikos-Rose

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.

Brain graphic

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)

Gene Discovery Pushes Back Origins of Insect Sense of Smell

By Kathy Keatley Garvey

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.

Defend Against Predators or Run? Evolutionary Tradeoffs in Butterflyfish

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.

Elastic Slingshot Powers Snipefish Feeding

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.

Shedding Light on the Energy-Efficiency of Photosynthesis

By Amy Quinton

Photosynthesis is one of the most crucial life processes on earth. It’s how plants get their food, using energy from sunlight to convert water and carbon dioxide from the air into sugars. It’s long been thought that more than 30 percent of the energy produced during photosynthesis is wasted in a process called photorespiration.

A new study led by researchers at the University of California, Davis, suggests that photorespiration wastes little energy and instead enhances nitrate assimilation, the process that converts nitrate absorbed from the soil into protein.

Study shows plants may not lose energy during photosynthesis. (Getty Images)

Playing It Cool at Ocean Vents

“Black smokers,” or high-temperature hydrothermal vents at the bottom of the ocean, have generated a lot of scientific interest since they were discovered forty years ago. By belching hot, mineral-laden water, these vents support communities of microbes and animals far from sunlight.

Octopuses incubate their eggs near the slightly warmer streams of water from cool hydrothermal vents deep in the ocean. Credit: Woods Hole Oceanographic Institution

But not all ocean vents are hot. Cool hydrothermal systems, or cool vents, are much harder to spot because the fluids they release are clear and only a bit warmer than surrounding water. Yet they could play a major role in releasing minerals into the deep ocean.

Of Mice and…Gorillas? Mouse Gene Catalog as a Conservation Tool

Gorilla

Mice share a similar set of genes to humans and gorillas. A catalog of the functions of all mouse genes could help in conservation efforts for endangered species.

A new study from the International Mouse Phenotyping Consortium, which includes the UC Davis Mouse Biology Program, shows how the growing catalog of mouse genes could be applied to save endangered species. The paper was published May 24 in the journal Conservation Genetics.

Data Dump: 11,000 Donate Stool Samples to Gut Microbiome Project

By Greg Watry

The American Gut Project has just produced the largest study yet of microbial diversity in human poop. With “contributions” from more than 11,000 citizen scientists, the team led by researchers at UC San Diego has compiled a public reference database on the human gut microbiome, published May 15 in the journal mSystems. The study is a step forward in understanding how factors such as diet, antibiotics and mental health relate to the microbes living in the human gut.

Biology Researchers Make Cell Metabolism “Best of 2017”           

Two different teams of researchers from the College of Biological Sciences are represented in the “Best of 2017” issue of the prominent journal Cell Metabolism. Their papers, on insulin-producing beta cells and on the effects of a low-carb diet on longevity in mice, are among just five research articles chosen to appear in the special issue along with two clinical reports and four review articles.

Pancreatic islet

Pancreatic islets make insulin in response to blood glucose. Mark Huising/UC Davis

Podcast: The Earth BioGenome Project

This month I talk to Professor Harris Lewin, one of the organizers of the Earth BioGenome Project. The ambitious project to sequence the genomes of all eukaryotic life on Earth within ten years is described in a paper published this week in the Proceedings of the National Academy of Sciences.

Listen: Three Minute Egghead: The Earth BioGenome Project

More information

Earth BioGenome Project Aims to Sequence DNA from All Complex Life on Earth (news release)

Earth BioGenome Project to Sequence All Life: Partnership Announced at World Economic Forum in Davos (news release)