Biology’s big bang had a long fuse: Animals started evolving long before showing up as fossils

Biology’s big bang had a long fuse: Animals started evolving long before showing up as fossils

A new effort to date the early history of modern animals finds a lot of evolutionary dawdling.

The last common ancestor of all living animals probably arose nearly 800 million years ago, a multidisciplinary research team reports in the Nov. 25Science. From that common ancestry, various animal lineages diverged and evolved on their own paths. Yet the major animal groups living today didn’t arise until roughly 200 million years later, in an exuberant burst of forms preserved in fossils during what’s called the Cambrian explosion.

Predators Drive Evolution Of Poison Dart Frogs’ Skin Patterns

Predators Drive Evolution Of Poison Dart Frogs’ Skin Patterns

Natural selection has played a role in the development of the many skins patterns of the tiny Ranitomeya imitator poison dart frog, according to a study that will be published in an upcoming edition of American Naturalist by University of Montreal biologist Mathieu Chouteau. The researcher’s methodology was rather unusual: on three occasions over three days, at two different sites, Chouteau investigated the number of attacks that had been made on fake frogs, by counting how many times that had been pecked. Those that were attacked the least looked like local frogs, while those that came from another area had obviously been targeted.

Researchers make the case that modern life sprang from early mega-organism

Researchers make the case that modern life sprang from early mega-organism

 A lot of work has been done over the years to nail down the origins of life, with much speculation given to whatever first bit of “life” appeared from what was before, nothing but non-living material. Unfortunately, evidence of such life has long vanished leaving researchers to try to piece together what might have happened afterwards by rewinding the genetic tape so to speak.

Life's diversity snowballed when Earth froze

Life's diversity snowballed when Earth froze

Ancient animals may have started their drive toward explosive diversity back when the Earth was a giant snowball, new research suggests. A startling expansion in the diversity of life forms began about 540 million years ago, early in the Cambrian period. During this apparently sudden outburst, known as the Cambrian explosion, all the major groups of animals seemed to materialize rapidly. Scientists have debated the causes of this great flowering of life for centuries.

Food We Eat Might Control Our Genes

Food We Eat Might Control Our Genes

“You are what you eat.” The old adage has for decades weighed on the minds of consumers who fret over responsible food choices. Yet what if it was literally true? What if material from our food actually made its way into the innermost control centers of our cells, taking charge of fundamental gene expression?

Ancient environment found to drive marine biodiversity

Ancient environment found to drive marine biodiversity

Much of our knowledge about past life has come from the fossil record – but how accurately does that reflect the true history and drivers of biodiversity on Earth? "It's a question that goes back a long way to the time of Darwin, who looked at the fossil record and tried to understand what it tells us about the history of life," says Shanan Peters, an assistant professor of geoscience at the University of Wisconsin–Madison. In fact, the fossil record can tell us a great deal, he says in a new study. In a report published Friday, Nov. 25 in Science magazine, he and colleague Bjarte Hannisdal, of the University of Bergen in Norway, show that the evolution of marine life over the past 500 million years has been robustly and independently driven by both ocean chemistry and sea level changes.

Worms Can Evolve to Survive Intersex Populations

Worms Can Evolve to Survive Intersex Populations

Sexually reproducing species need at least two sexes in order to produce offspring, but there are many ways that nature produces different sexes. Many animals (including humans and other mammals) use a chromosomal sex determination system in which females have two X chromosomes, while males have one X and one Y.

Soft food may lead to a mouth with too many teeth

Soft food may lead to a mouth with too many teeth

Teenagers facing the purgatory of braces to fix their misaligned teeth might be able to blame bread for their predicament. Noreen von Cramon-Taubadel at the University of Kent, UK, measured the shape of 295 human lower jaws from museum specimens. Those that came from agricultural societies were smaller, on average, than those that came from hunter-gatherer societies – although all carried the same number of teeth.

Predators Drive Evolution Of Poison Dart Frogs’ Skin Patterns

Predators Drive Evolution Of Poison Dart Frogs’ Skin Patterns

Natural selection has played a role in the development of the many skins patterns of the tiny Ranitomeya imitator poison dart frog, according to a study that will be published in an upcoming edition of American Naturalist by University of Montreal biologist Mathieu Chouteau. The researcher’s methodology was rather unusual: on three occasions over three days, at two different sites, Chouteau investigated the number of attacks that had been made on fake frogs, by counting how many times that had been pecked. Those that were attacked the least looked like local frogs, while those that came from another area had obviously been targeted.

Sex explains why the fit don't always survive

Sex explains why the fit don't always survive

 New research from The Australian National University has shown how genetic variation persists through generations, rather than being bred out in an evolution towards a ‘perfect type’.

Study of flower petals shows evolution at the cellular level

Study of flower petals shows evolution at the cellular level

A new study of flower petals shows evolution in action, and contradicts more that 60 years of scientific thought.

The findings are reported by a scientist from UC Santa Barbara and a research team from Harvard University in the Proceedings of the Royal Society B this week. Columbine flowers, known as Aquilegia, evolved several lengths of petal spurs that match the tongue lengths of their pollinators, including bees, hummingbirds, and hawkmoths. The petal spurs are shaped like a tubular pocket and contain nectar at the tip. The spurs grow from 1 to 16 centimeters in length, depending on the species.

Darwin’s Tongues Languages, like genes, can tell evolutionary tales

Darwin’s Tongues Languages, like genes, can tell evolutionary tales

Talk is cheap, but scientific value lurks in all that gab. Words cascading out of countless flapping gums contain secrets about the evolution of language that a new breed of researchers plan to expose with statistical tools borrowed from genetics.

The first hairy microbes: New fossils reveal oldest known ciliates

The first hairy microbes: New fossils reveal oldest known ciliates

MIT researchers have found hundreds of tiny fossils of the first known ciliates. The ciliates, named tintinnids, resided in hard, flask-shaped shells with bubbled exteriors that likely help them float. Image: Tanja Bosak

The Evolution of Grief, Both Biological and Cultural, in the 21st Century

The Evolution of Grief, Both Biological and Cultural, in the 21st Century

Three months ago, I received an email informing me that a high school friend, Pat, had died.

I read his obituary and my body stopped functioning. I froze on the spot, limbs tense but trembling. My mouth went dry, my vision blurred. As I waited for my train in the packed station, I could barely stand as my muscles turned to jelly and legs folded beneath my body. I tried to maintain composure in the public space, but my contorted face betrayed my sorrow.

Proof the Universe is Fine-Tuned for Life? Scientists Find Antarctica Meteorites Contain Essential Building Block of DNA

Proof the Universe is Fine-Tuned for Life? Scientists Find Antarctica Meteorites Contain Essential Building Block of DNA

NASA-funded researchers found evidence this past summer that some building blocks of DNA, the molecule that carries the genetic instructions for life, found in meteorites were likely created in space. The research gives support to the theory that a "kit" of ready-made parts created in space and delivered to Earth by meteorite and comet impacts assisted the origin of life.

Human-induced fires sow the seeds of the future

Human-induced fires sow the seeds of the future

Human-made fires are influencing the evolutionary process of some plant species' seeds, a study has shown.

Scientists found that seeds that were less rounded and coated in thicker protective hairs were more likely to survive fires used to clear scrub.

The study was carried out in an area where natural fires were very rare, allowing the researchers to analyse the impact of human activity.

Evolution: The Curious Case of Dogs

Link: Evolution: The Curious Case of Dogs

This is the first in a series of post of mine about Evolution that I started posting in January of 2010. I’ll be reposting the series over the next two months, culminating in a brand new post for the set in Jan 2012! I’m excited. You know you’re excited. Enjoy!

Man’s best friend is much more than a household companion – for centuries, artificial selection in dogs has made them prime examples of the possibilities of evolution. A century and a half ago, Charles Darwin recognized how the incredibly diverse dogs supported his revolutionary theory in his famous book On The Origin Of Species. At the time, he believed that dogs varied so much that they must have been domesticated from multiple canine species. Even still, he speculated that:

So where do we get the energy to run our big brains? Reduced gut size? More body fat? The way we move? Debate rages on despite new data

Link: So where do we get the energy to run our big brains? Reduced gut size? More body fat? The way we move? Debate rages on despite new data

Half a million years ago, the human brain started expanding. Bigger brains need more energy to keep trucking, but scientists have been stumped as to where we found this extra juice when our metabolic rate, which is how we churn out energy, is on par with our pea-brained cousins.

One recent theory suggests that our brain’s need for energy was fed by a smaller gut, since an easier-to-digest diet would free up energy from the gut to build up the brain. New research suggests this might not be the case, that storing energy in our fat deposits is more important.

Study finds cooking increases energy from meat, may have driven human evolution

Link: Study finds cooking increases energy from meat, may have driven human evolution

In a first-of-its kind study, Harvard researchers have shown that cooked meat provides more energy than raw meat, a finding that suggests humans are biologically adapted to take advantage of the benefits of cooking, and that cooking played a key role in driving the evolution of man from an ape-like creature into one more closely resembling modern humans.

Conducted by Rachel Carmody, a student in Department of Human Evolutionary Biology at Harvard’s Graduate School of Arts and Sciences and described in the Proceedings of the National Academy of Sciences(PNAS), the research also raises important questions about the way modern humans eat.

The Lost Eukaryote: an introduction to cellular evolution

Link: The Lost Eukaryote: an introduction to cellular evolution

The most fundamental divide in the diversity of living creatures is arguably the one between prokaryotes (=bacteria*) and eukaryotes (the tiny island of cumbersomely complex cells that consists of protists. And a couple insignificant lineages that are hardly worth talking about). Much of the earth’s biota seems perfectly content with small, streamlined genomes and similarly small, streamlined cell architecture. All but one group, that for some odd reason ended up with a membrane-bound package of a junky genome we call the nucleus.