Paleontologists studying fossilized feathers have proposed that the shapes of certain microscopic structures inside the feathers can tell us the color of ancient birds. But new research from North Carolina State Univ. demonstrates that it is not yet possible to tell if these structures, thought to be melanosomes, are what they seem, or if they are merely the remnants of ancient bacteria.
For four decades, polychlorinated biphenyls (PCBs...
The largest mass extinction in the history of animal life occurred some 252 million years ago,...
When people see a skunk, the reaction usually is “...
A substantial fraction of the Neanderthal genome persists in modern human populations. A new approach applied to analyzing whole-genome sequencing data from 665 people from Europe and East Asia shows that more than 20% of the Neanderthal genome survives in the DNA of this contemporary group, whose genetic information is part of the 1,000 Genomes Project.
Insects may thrive in the warmer average temperatures predicted by climate models but are threatened by greater temperature variation also anticipated in many areas around the globe, a Yale Univ.-led study predicts. Scientists have tested the impact of temperature on 38 species of insects. The team coupled that data with historic climate data and climate projections for 2050 to 2059 in order to assess effects of temperature variability.
An international team of scientists have examined the earliest communities of large multicellular organisms in the fossil record to help answer this question of why life forms began to get larger about 580 million years ago. The research reveals that an increase in size provided access to nutrient-carrying ocean flow, giving an advantage to multicellular eukaryotes that existed prior to the Cambrian explosion of animal life.
"Where do new genes come from?" is a long-standing question in genetics and evolutionary biology. A new study from researchers at the Univ. of California, Davis, published in Science Express, shows that new genes are created from non-coding DNA more rapidly than expected.
A closer look at microbes reveals there is big business going on in their very small world, and sometimes we are part of the transaction. In a published report, an international team of researchers argue that microbes, like many animals, can evolve into savvy traders, selling high and buying low.
One of the most hotly debated issues in current human origins research focuses on how the 4.4-million-year-old African species Ardipithecus ramidus is related to the human lineage. “Ardi” was an unusual primate. Though it possessed a tiny brain and a grasping big toe used for clambering in the trees, it had small, humanlike canine teeth and an upper pelvis modified for bipedal walking on the ground.
An international research team has produced a high-quality genome sequence of a Neanderthal woman from a toe bone found in 2010 by Russian archaeologists. The genome will allow detailed insights into the relationships and population history of the Neanderthals and other extinct hominin groups.
Interplay between genes and the environment has been pondered at least since the mid-1800s. But until the arrival of modern genomic sequencing tools, it was hard to measure the extent that the environment had on a species’ genetic makeup. Now, researchers studying fruit flies that live on opposite slopes of a unique natural environment known as “Evolution Canyon” show the driving force in the gene pool is largely the environment.
Rain as acidic as undiluted lemon juice may have played a part in killing off plants and organisms around the world during the most severe mass extinction in Earth’s history. About 252 million years ago, the end of the Permian period brought about a worldwide collapse known as the Great Dying, during which a vast majority of species went extinct. The cause of such a massive extinction is a matter of scientific debate.
Scripps Institution of Oceanography researchers are unraveling the mechanisms behind a little-known marine worm that produces a dazzling bioluminescent display in the form of puffs of blue light released into seawater. This effect, produced by mucus, hasn’t been studied in more than 50 years. But two recent studies have helped reignite the quest to decode the inner workings of the worm’s bioluminescence.
Earth’s oldest sedimentary rocks are not only rare, but also almost always altered by hydrothermal and tectonic activity. The Pilbara district in Australia is a rare exception. A new study has revealed the well-preserved remnants of a complex ecosystem in a nearly 3.5 billion-year-old sedimentary rock sequence.
Scientists have puzzled for centuries over how and why multicellular organisms evolved the almost universal trait of using single cells, such as eggs and sperm, to reproduce. Now, researchers have set a big piece of that puzzle into place by applying experimental evolution to transform a single-celled algae into a multicellular one that reproduces by dispersing single cells.
Digs over the years at the La Brea Tar Pits in the heart of Los Angeles have unearthed bones of mammoths, mastodons, saber-toothed cats and dire wolves that became trapped in ponds of sticky asphalt. But it's the smaller discoveries, like plants, insects and rodents, that in recent years are shaping scientists' views of life in the region 11,000 to 50,000 years ago.
A British scientist says he may have solved the mystery of the Abominable Snowman, the elusive ape-like creature of the Himalayas. DNA analysis conducted by Oxford Univ. genetics professor Bryan Sykes suggests the creature, also known as the Yeti, is the descendant of an ancient polar bear.
The discovery of a 1.8-million-year-old skull of a human ancestor buried under a medieval Georgian village provides a vivid picture of early evolution and indicates our family tree may have fewer branches than some believe, scientists say. The fossil is the most complete pre-human skull uncovered.
Enhanced growth of Earth's leafy greens during the 20th century has significantly slowed the planet's transition to being red-hot, according to the first study to specify the extent to which plants have prevented climate change since pre-industrial times. Researchers based at Princeton Univ. found that land ecosystems have kept the planet cooler by absorbing billions of tons of carbon, especially during the past 60 years.
Darwin referred to the origin of species as "that mystery of mysteries," and even today, more than 150 years later, evolutionary biologists cannot fully explain how new animals and plants arise. For decades, nearly all research in the field has been based on the assumption that the main cause of the emergence of new species, a process called speciation, is the formation of barriers to reproduction between populations. Until now.
Steven Benner of Westheimer Institute for Science and Technology will tell geochemists gathering Thursday at the annual Goldschmidt conference that an oxidized mineral form of the element molybdenum, which may have been crucial to the origin of life, could only have been available on the surface of Mars and not on Earth.
Communities in nature are likely to be a lot more sensitive to change than previously thought, according to a new study at Rice Univ. The study shows that scientists concerned about human influence on the biosphere need to take a deeper look at how altering the dynamics of a population—for example, by removing large members of a species through overfishing—can have measurable consequences.
Out of the estimated 23,000 or more genes in the human genome, about 100 of them will differ, they will be present or not, between any two individuals. Genes lost or gained over time result from evolution and adaptation, as species respond through the years to their environment and other influences.
Sugars are important sources of energy for all organisms. Virginia Tech researchers have discovered that certain types of sugars, known as polysaccharides, may also control the timing and placement of minerals that animals use to produce hard structures such as shells and exoskeletons of mollusks, lobsters, and shrimp.
The chemical components crucial to the start of life on Earth may have primed and protected each other in never-before-realized ways, according to new research led by Univ. of Washington scientists. It could mean a simpler scenario for how that first spark of life came about on the planet.
In a twist on "survival of the fittest," researchers have discovered that evolution is driven not by a single beneficial mutation but rather by a group of mutations, including ones called "genetic hitchhikers" that are simply along for the ride. These hitchhikers are mutations that do not appear to have a role in contributing to an organism's fitness and therefore its evolution, yet may play an important role down the road.
A new mathematical theory from the Univ. of Bath is challenging one of the most basic ideas of biology—that the concept of a ‘species’ applies to all creatures. The new results suggest that classifying very small creatures from extremely large populations into species may actually be impossible. This is because for large populations, the gradual build-up over time of random genetic mutations leads to an overwhelming amount of diversity.
At the end of the last Ice Age, as the world began to warm, a brief pulse of biological productivity in the Pacific Ocean gave rise to large numbers of phytoplankton, foraminifera and other creatures. Researchers have hypothesized that iron sparked this surge of ocean life, but a new study determines instead that “perfect storm” of nutrients and light spurred the bloom.
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