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The exceptionally well-preserved fossil primate known as "Ida" is not a missing link as some have claimed, according to an analysis in the journal Nature. The research is the first independent assessment of the claims made in a scientific paper and a television documentary earlier this year. Dr Erik Seiffert says that Ida belonged to a group more closely linked to lemurs than to monkeys, apes or us. His team's conclusions come from an analysis of another fossil primate. The newly described animal - known as Afradapis longicristatus - lived some 37 million years ago in northern Egypt, during the...

Scientists at the Georgia Institute of Technology have found genetic evidence that seems to support a controversial hypothesis that humans and chimpanzees may be more closely related to each other than chimps are to the other two species of great apes – gorillas and orangutans. They also found that humans evolved at a slower rate than apes. Appearing in the January 23, 2006 issue of the Proceedings of the National Academy of Sciences, biologist Soojin Yi reports that the rate of human and chimp molecular evolution – changes that occur over time at the genetic level – is much slower...

The brains of chimpanzees show a number of similarities to human brains, the results of two new studies suggest. Findings published in the December issue ofBehavioral Neuroscience indicate that the animals have differences between the right and left sides of their brains in much the same way that humans do. In addition, it appears that the neurological basis for handedness is not unique to our species. Hani D. Freeman of the Yerkes National Primate Research Center and his colleagues scanned the brains of 60 chimpanzees with magnetic resonance imaging (MRI) and measured two key regions of the brain's limbic system,...

By Clive Cookson, Science Editor Published: August 31 2005 18:46 | Last updated: August 31 2005 18:46 The first detailed genetic comparison between humans and chimpanzees shows that 96 per cent of the DNA sequence is identical in the two species. But there are significant differences, particularly in genes relating to sexual reproduction, brain development, immunity and the sense of smell. An international scientific consortium publishes the genome of the chimpanzee, the animal most closely related to homo sapiens on Thursday in the journal Nature. It is the fourth mammal to have its full genome sequenced, after the mouse, rat...

Despite decades of study, geneticists don't know what makes humans human. Language, long arms, and tree-climbing prowess aside, humans and our kissing cousins, chimpanzees, share practically all of our DNA. Genomic studies have suggested that the regulation of genes, rather than the genes themselves, set the two primate species apart. But genes are still an important part of the story, says Michele Cargill, a geneticist at Celera Diagnostics in Alameda, California. She and her colleagues found key differences between chimp and human genome coding sequences, differences that propelled human evolution and sometimes lead to genetic diseases. Genes for olfaction and...

Why the Y chromosome is a hotbed for evolution Mark Henderson, Science Editor The Y chromosome is often seen as the rotten corner of the human genome — a place of evolutionary decline that is slowly decaying and threatening the end of man. Reports of its imminent demise, however, have been exaggerated. Research has indicated that, far from stagnating, the male chromosome is a hotspot of evolution that is changing more quickly than any other part of humanity’s genetic code. In most mammals the sex of offspring is determined by X and Y chromosomes. Females have two Xs, males have...

A group of researchers from Korea and Japan has deciphered the Y chromosome of chimpanzees' genetic code, getting a step closer to solving the mysteries surrounding human evolution. It is well known that we share more than 98 percent of our DNA and almost all of our genes with the chimpanzee. Now the researchers have decoded more than half of the Y chromosomes, or 12.7 million base pairs, of man's closest living relative. "Because no genetic exchange occurs, the Y chromosome is important in explaining the evolution process," said Park Hong-seog, a senior researcher at the Korea Research Institute of...

Since the human-chimp split about 6 million years ago, chimpanzee genes can be said to have evolved more than human genes, a new study suggests. The results, detailed online this week in the Proceedings of the National Academy of Sciences, contradict the conventional wisdom that humans are the result of a high degree of genetic selection, evidenced by our relatively large brains, cognitive abilities and bi-pedalism. Jianzhi Zhang of the University of Michigan and his colleagues analyzed strings of DNA from nearly 14,000 protein-coding genes shared by chimps and humans. They looked for differences gene by gene and whether they...

Probable life appearance in anterior view of Ardipithecus ramidus ("Ardi"), ARA-VP 6/500.Photograph by: Handout, Illustrations 2009, J.H. Matternes An international team of scientists unveiled Thursday the results of 15 years of study of one of the oldest known human ancestors, Ardipithecus ramidus, which they say overturns much of what we know about human evolution. And surprisingly, it's also rewriting the story of our relation to gorillas and chimpanzees, our closest living relatives, and their development as well. Yohannes Haile-Selassie, one of the authors involved in the research and the man who discovered the first pieces of the most complete...

Each poo is a time capsule to the dawn of the dinosaurs. A gigantic "communal latrine" created at the dawn of the dinosaurs has been unearthed in Argentina. Thousands of fossilised poos left by rhino-like megaherbivores were found clustered together, scientists say. The 240-million-year-old site is the "world's oldest public toilet" and the first evidence that ancient reptiles shared collective dumping grounds. The dung contains clues to prehistoric diet, disease and vegetation says a study in Scientific Reports. Continue reading the main story [snip]

Flower Fossils 100,000,000 Years Out of Place? by Brian Thomas, M.S. * European scientists have now discovered flowering plant fossils in rock layers supposedly 100,000,000 years older than expected.1 This new finding challenges conventional evolutionary assumptions as scientists struggle to account for what they interpret as an enormous time gap. Publishing in the journal Frontiers in Plant Science, Peter Hochuli and Susanne Feist-Burkhardt described fossil-pollen grains recovered from a drill core in the north of Switzerland.1 They wrote, "In this paper we focus on fossil evidence, presenting the so far oldest angiosperm-like pollen from the Middle Triassic (ca. 243Ma), a...

Two fossils have got palaeontologists scratching their heads about where to place an enigmatic group of animals in the mammalian family tree. A team analysing one fossil suggests that the group belongs in mammals, but researchers looking at the other propose that its evolutionary clan actually predates true mammals. The situation begs for more analysis, more fossils, or both, experts say. The fossils represent previously unknown species, described today in Nature1, 2. Both are members of the haramiyids, a group of animals that first appeared around 212 million years ago and that researchers first recognized in the late 1840s. Until...

Can This Dog Sniff Out Fossils? by Brian Thomas, M.S. * Gary Jackson and his dog Migaloo, trained to sniff out buried remains, work with locals to uncover archaeological sites and help Australian police locate the bodies of murder victims. According to The Sydney Morning Herald, "Migaloo quickly located the 600-year-old remains of an indigenous Australian,"1 which researchers found a decade ago. But that specialized training resulted in an unforeseen crossover—Migaloo can also smell fossils. Fossils are supposed to be rocks in the shape of bones, with no original bone material remaining. Over supposed eons, gradually trickling minerals slowly replaced...

"... A recent discovery by Dr. Mary Schweitzer, however, has given reason for all but committed evolutionists to question this assumption. Bone slices from the fossilized thigh bone (femur) of a Tyrannosaurus rex found in the Hell Creek formation of Montana were studied under the microscope by Schweitzer. To her amazement, the bone showed what appeared to be blood vessels of the type seen in bone and marrow, and these contained what appeared to be red blood cells with nuclei, typical of reptiles and birds (but not mammals). The vessels even appeared to be lined with specialized endothelial cells found...

Scientists have revealed insights into a peculiar, phallus-shaped creature discovered at a fossil site in Canada. The animal has been identified as Spartobranchus tenuis, a species from the Cambrian period that was previously unknown to science. The odd-looking creature was an ancient relative of acorn worms that exist today, according to researchers. Their study, published in the journal Nature, is the first full description of the prehistoric animal. Remains of soft-bodied worms were found in the Burgess Shale fossil beds in Yoho National Park, British Columbia, Canada throughout the last century. But now researchers studying the 505 million years old...

Cryptic comments seem to have an ambiguous, obscure or hidden meaning. In biology, cryptic species are outwardly indistinguishable groups whose differences are hidden inside their genes. Two University of Michigan marine biologists have identified three cryptic species of tiny clams, long believed to be members of the same species, which have been hiding in plain view along the rocky shores of southern Australia for millions of years. The unusual convergence of a climate-cooling event and the peculiarities of local geography caused the three cryptic species to split from a common ancestor more than 10 million years ago, the U-M researchers...

Researchers Just Dug Up A Half-Million-Year-Old Human Jawbone Tia Ghose, LiveScienceFebruary, 2013 . An ancient hominin jawbone unearthed in a Serbian cave may be more than half a million years old. Scientists have unearthed a jawbone from an ancient human ancestor in a cave in Serbia. The jawbone, which may have come from an ancient Homo erectus or a primitive-looking Neanderthal precursor, is more than 397,000 years old, and possibly more than 525,000 years old. The fossil, described today (Feb. 6) in the journal PLOS ONE, is the oldest hominin fossil found in this region of Europe, and may change...

Chinese researchers have tracked the "exceptionally well-preserved fossils" to the Middle Triassic of China (235-242 million years ago). The Triassic period saw the re-establishment of ecosystems after the Permian mass extinction. The fossils represent new evidence that marine ecosystems re-established more quickly than previously thought. The Permian mass extinction had a bigger impact on the earth's ecological systems than any other mass extinction, wiping out 90-95% of marine species. Previous studies have suggested that Triassic marine life developed more quickly than was once thought and that marine ecosystems were re-established more rapidly than terrestrial ecosystems... The fossils show an asymmetrical,...

The behaviour of an ancient horseshoe crab in its final moments before death has been captured in the fossil record. A 9.7m-long trackway was created around 150 million years ago when a horseshoe crab fell into a lagoon. The find is of interest because the fossil of the animal itself is present at the end of the trackway, where the animal died. The research appears in the journal Ichnos. The fossil trackway of the animal's last moments - known as a mortichnia, or death march - was discovered in the lithographic limestone of Bavaria in Germany in 2002, where spectacular...

These 230-million-year-old bugs preserved in amber are the oldest yet An international team of scientists working in Italy have found the oldest samples of arthropods preserved in amber — a finding that is 100 million years older than previous fossilized samples. The insects, a fly and two mites, are the first ever to be discovered from the Triassic era. The group's findings will help biologists gain a better evolutionary understanding of these organisms and the time periods within which they developed. Amber droplets can be a goldmine for paleontologists. Even a millimeter sized droplet can contain extremely well preserved specimens...