PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Darwin's dilemma resolved: Evolution's 'big bang' explained by 5x faster rates

2013-09-12
(Press-News.org) The incredible burst of innovation in animals' body plans and habits during the Cambrian explosion, between 540 and 520 million years ago, can be explained by a reasonable uptick in evolutionary rates. The discovery, based on the first rigorous estimates of early evolutionary rates in arthropods, shows that evolution's "big bang" is compatible with natural selection as Darwin envisioned it, say researchers reporting their findings in Current Biology, a Cell Press publication, on September 12.

"This simultaneous burst of life, with few or no precursors, had seemed at odds with Darwin's idea of gradual evolution through natural selection," says Mike Lee from the University of Adelaide in Australia. "However, our results show that moderately accelerated evolution, sustained over a few tens of millions of years, could have produced this pattern. A five-fold increase in rates of evolution would compress about 100 million years' worth of change into about 20 million years—a relatively brief period in geological terms."

The researchers considered arthropods—the group including insects, spiders, and crustaceans—because they were the most diverse and successful animals during the Cambrian explosion and remain so today. Arthropods currently account for more than 80 percent of all animal species.

"To a first approximation, every animal species is an arthropod!" Lee says. "If we are interested in major patterns in animal evolution, arthropods are the key group to study."

With the help of the fossil record and molecular dating methods, Lee and his colleagues quantified the anatomical and genetic differences between living arthropods to infer evolutionary rates in the past. Their analysis shows that evolutionary change during the Cambrian period occurred about four to five times faster than present-day rates. They were surprised to see that genetic evolution and anatomical evolution were sped up by almost the same amount during the Cambrian.

Lee explains that those faster evolutionary rates are likely explained by game-changing innovations—predation, vision, and active swimming, for instance—that opened up a range of new possibilities for arthropods during the Cambrian. That kind of evolutionary fast-forward has also occurred when animals colonize new environments, he says. Think birds or mammals on islands, or snakes in the sea.

"When a lineage acquires a novel adaptation, they often undergo a burst of evolution, to fill up a newly opened range of environments and niches," Lee says.



INFORMATION:



Current Biology, Lee et al.: "Rates of Phenotypic and Genomic Evolution during the Cambrian Explosion."



ELSE PRESS RELEASES FROM THIS DATE:

Study sheds light on genetics of how and why fish swim in schools

2013-09-12
SEATTLE – How and why fish swim in schools has long fascinated biologists looking for clues to understand the complexities of social behavior. A new study by a team of researchers at Fred Hutchinson Cancer Research Center may help provide some insight. To be published online in the Sept. 12 issue of Current Biology, the study found that two key components of schooling – the tendency to school and how well fish do it – map to different genomic regions in the threespine stickleback, a small fish native to the Northern Hemisphere. That's important, said lead author Anna ...

Autism gene stunts neurons, but growth can be restored, in mice

2013-09-12
PROVIDENCE, R.I. [Brown University] — Brown University researchers have traced a genetic deficiency implicated in autism in humans to specific molecular and cellular consequences that cause clear deficits in mice in how well neurons can grow the intricate branches that allow them to connect to brain circuits. The researchers also show in their study (online Sep. 12, 2013, in Neuron) that they could restore proper neuronal growth by compensating for the errant molecular mechanisms they identified. The study involves the gene that produces a protein called NHE6. Mutation ...

New info on an elusive green cicada

2013-09-12
For nearly 80 years, the North American cicada Okanagana viridis has received little attention in scientific literature, but a new article in the Annals of the Entomological Society of America provides the first notes on the song and ecology of this elusive species, and updates its known range. O. viridis is unusual in a large genus of 60 otherwise arid- or cold-adapted, mostly western U.S. species, in that it is found in the temperate deciduous southern forests of Arkansas, Louisiana, Mississippi, Tennessee, and Texas. It is almost solid bright green, and it calls from ...

La Jolla Institute scientist identifies helper cells that trigger potent responses to HIV

2013-09-12
SAN DIEGO – (September 12, 2013) A major new finding that will significantly advance efforts to create the world's first antibody-based AIDS vaccine was published today by researchers from the La Jolla Institute for Allergy and Immunology. La Jolla Institute scientist Shane Crotty, Ph.D., a respected vaccine researcher and member of one of the nation's top AIDS vaccine consortiums, showed that certain helper T cells are important for triggering a strong antibody response against HIV, the virus that causes AIDS. Helper T cells are disease-fighting immune cells key in ...

A microbe's trick for staying young

2013-09-12
Researchers have discovered a microbe that stays forever young by rejuvenating every time it reproduces. The findings, published in Current Biology, provide fundamental insights into the mechanisms of aging. While aging remains an inevitable fact of life, an international team involving researchers from the University of Bristol and the Max-Planck Institute for Molecular Cell Biology and Genetics in Germany has found that this is not the case for a common species of yeast microbe which has evolved to stay young. The team has shown that, unlike other species, the ...

Dali gets a health check: Using medical devices to diagnose art

2013-09-12
Scientists and conservators have developed a new method to diagnose painting canvases from the back, without disturbing a single fibre, to see if they can withstand the stress of handling and travel. Using the method - which is similar to the way doctors measure blood sugar without the need for needles – scientists examined 12 paintings by the surrealist painter Salvador Dalí. They assessed the 'health' of the canvases, which are known to degrade with time due to acidity and environmental conditions. Once a canvas is brittle, expensive conservation is required. While ...

Biologists measure evolution's Big Bang

2013-09-12
A new study led by Adelaide researchers has estimated, for the first time, the rates of evolution during the "Cambrian explosion" when most modern animal groups appeared between 540 and 520 million years ago. The findings, published online today in the journal Current Biology, resolve "Darwin's dilemma": the sudden appearance of a plethora of modern animal groups in the fossil record during the early Cambrian period. "The abrupt appearance of dozens of animal groups during this time is arguably the most important evolutionary event after the origin of life," says lead ...

The peanut at the heart of our galaxy

2013-09-12
One of the most important and massive parts of the galaxy is the galactic bulge. This huge central cloud of about 10 000 million stars spans thousands of light-years, but its structure and origin were not well understood. Unfortunately, from our vantage point from within the galactic disc, the view of this central region — at about 27 000 light-years' distance — is heavily obscured by dense clouds of gas and dust. Astronomers can only obtain a good view of the bulge by observing longer wavelength light, such as infrared radiation, which can penetrate the dust clouds. Earlier ...

Probing methane's secrets: From diamonds to Neptune

2013-09-12
Washington, D.C.—Hydrocarbons from the Earth make up the oil and gas that heat our homes and fuel our cars. The study of the various phases of molecules formed from carbon and hydrogen under high pressures and temperatures, like those found in the Earth's interior, helps scientists understand the chemical processes occurring deep within planets, including Earth. New research from a team led by Carnegie's Alexander Goncharov hones in on the hydrocarbon methane (CH4), which is one of the most abundant molecules in the universe. Despite its ubiquity, methane's behavior ...

Protein essential for maintaining beta cell function identified

2013-09-12
Researchers at the Pediatric Diabetes Research Center (PDRC) at the University of California, San Diego School of Medicine have shown that the pancreatic protein Nkx6.1 – a beta-cell enriched transcription factor – is essential to maintaining the functional state of beta cells. Type 2 diabetes is characterized by impaired insulin secretion by pancreatic beta cells in response to a rise in blood glucose levels. The study, published in the September 26 edition of Cell Reports, shows that loss of NKx6.1 in mice caused rapid onset diabetes. UC San Diego scientists – ...

LAST 30 PRESS RELEASES:

Community partners key to success of vaccine clinic focused on neurodevelopmental conditions

Low-carbon collaborative dual-layer optimization for energy station considering joint electricity and heat demand response

McMaster University researchers uncover potential treatment for rare genetic disorders

The return of protectionism: The impact of the Sino-US trade war

UTokyo and NARO develop new vertical seed distribution trait for soybean breeding

Research into UK’s use of plastic packaging finds households ‘wishcycle’ rather than recycle – risking vast contamination

Vaccine shows promise against aggressive breast cancer

Adverse events affect over 1 in 3 surgery patients, US study finds

Outsourcing adult social care has contributed to England’s care crisis, argue experts

The Lancet: Over 800 million adults living with diabetes, more than half not receiving treatment, global study suggests

New therapeutic approach for severe COVID-19: faster recovery and reduction in mortality

Plugged wells and reduced injection lower induced earthquake rates in Oklahoma

Yin selected as a 2024 American Society of Agronomy Fellow

Long Covid could cost the economy billions every year

Bluetooth technology unlocks urban animal secrets

This nifty AI tool helps neurosurgeons find sneaky cancer cells

Treatment advances, predictive biomarkers stand to improve bladder cancer care

NYC's ride-hailing fee failed to ease Manhattan traffic, new NYU Tandon study reveals

Meteorite contains evidence of liquid water on Mars 742 million years ago

Self-reported screening helped reduce distressing symptoms for pediatric patients with cancer

Which risk factors are linked to having a severe stroke?

Opening borders for workers: Abe’s profound influence on Japan’s immigration regime

How skills from hospitality and tourism can propel careers beyond the industry

Research shows managers of firms handling recalls should review media scrutiny before deciding whether to lobby

New model system for the development of potential active substances used in condensate modifying drugs

How to reduce social media stress by leaning in instead of logging off

Pioneering research shows sea life will struggle to survive future global warming

In 10 seconds, an AI model detects cancerous brain tumor often missed during surgery 

Burden of RSV–associated hospitalizations in US adults, October 2016 to September 2023

Repurposing semaglutide and liraglutide for alcohol use disorder

[Press-News.org] Darwin's dilemma resolved: Evolution's 'big bang' explained by 5x faster rates