Archaeology News Online

By analyzing the DNA of two prehistoric dogs from Germany, an international research team led by Krishna R. Veeramah, PhD, Assistant Professor of Ecology & Evolution in the College of Arts & Sciences at Stony Brook University, has determined that their genomes were the probable ancestors of modern European dogs. The finding, to be published in Nature Communications , suggests a single domestication event of modern dogs from a population of gray wolves that occurred between 20,000 and 40,000 years ago. The 5000 year old Late Neolithic CTC dog skull in the lab before it underwent whole genome sequencing  [Credit: Amelie Scheu] Dogs were the first animal to be domesticated by humans. The oldest dog fossils that can be clearly distinguished from wolves are from the region of what is now Germany from around 15,000 years ago. However, the archaeological record is ambiguous, with claims of ancient domesticated dog bones as far east as Siberia. Recent analysis of genetic data from ...

For three years, Tara Djokic, a Ph.D. student at the University of New South Wales Sydney, scoured the forbidding landscape of the Pilbara region of Western Australia looking for clues to how ancient microbes could have produced the abundant stromatolites that were discovered there in the 1970s. Conical stromatolite (view from the top) at the Trendall locality in the Pilbara  [Credit: © Government of Western Australia] Stromatolites are round, multilayered mineral structures that range from the size of golf balls to weather balloons and represent the oldest evidence that there were living organisms on Earth 3.5 billion years ago. Scientists who believed life began in the ocean thought these mineral formations had formed in shallow, salty seawater, just like living stromatolites in the World Heritage-listed area of Shark Bay, which is a two-day drive from the Pilbara. But what Djokic discovered amid the strangling heat and blood-red rocks of the region was evidence that the stromato...

Male live-bearing fish are evolving faster than female fish, according to a Kansas State University study, and that's important for understanding big-picture evolutionary patterns. Samples of fish species from the Poeciliidae family show the diversity in color, fin size and body shape.  Kansas State University researchers studied 112 species of these live-bearing fishes and found that  males and females evolve differently [Credit: Kansas State University] Researchers Michael Tobler, associate professor of biology, and Zach Culumber, former university postdoctoral research associate and current postdoctoral researcher at Florida State University, studied 112 species of live-bearing fish and found that males and females evolve differently: Female evolution is influenced more strongly by natural selection and the environment, while male evolution is influenced more strongly by sexual selection, which involves characteristics that females find desirable or that make them superior ...

No other animal on land is faster than a cheetah -- the elephant is indeed larger, but slower. For small to medium-sized animals, larger also means faster, but for really large animals, when it comes to speed, everything goes downhill again. For the first time, it is now possible to describe how this parabola-like relationship between body size and speed comes about. A research team under the direction of the German Centre for Integrative Biodiversity Research (iDiv) and the Friedrich Schiller University Jena (Germany) have managed to do so thanks to a new mathematical model, and also published their findings in the journal Nature Ecology and Evolution . The African elephant is the largest animal on land, but not the fastest. There is a parabola-like relationship between the  body mass of animals and the maximum speed they can reach. For the first time, researchers are able to describe how  this comes about, thanks to a simple mathematical model [Credit: Bernd Adam] A beetle i...

More species of birds have accumulated in genera inhabiting climatically stable areas. This is shown by a new study from Umea University. Bar-tailed Godwit [Credit: Umea University] "The explanation may be that a stable climate makes it more likely that diverging lineages persist without going extinct or merging until speciation is completed, and stability reduces the risk for extinction in response to climatic upheavals," says Roland Jansson, researcher from Umea University who led the study. How life has evolved from simple origins into millions of species is a central question in biology that remains unsolved. Advances in genomics and bioinformatics mean we now know a lot about the relationships among species and their origins, but surprisingly little is known about which environmental conditions that allows species to multiply. In a project focusing on how climate changes in the past affects the evolution of biodiversity, researchers tried to fill this knowledge gap. They...

The world's most indestructible species, the tardigrade, an eight-legged micro-animal, also known as the water bear, will survive until the Sun dies, according to a new Oxford University collaboration. The tardigrade, also known as the water bear, is the toughest, most resilient, form of life on Earth  [Credit: Shutterstock] The new study published in Scientific Reports , has shown that the tiny creatures, will survive the risk of extinction from all astrophysical catastrophes, and be around for at least 10 billion years -- far longer than the human race. Although much attention has been given to the cataclysmic impact that an astrophysical event would have on human life, very little has been published around what it would take to kill the tardigrade, and wipe out life on this planet. The research implies that life on Earth in general, will extend as long as the Sun keeps shining. It also reveals that once life emerges, it is surprisingly resilient and difficult to destroy, opening...

Ciliates, just like humans, are colonized by a vast diversity of bacteria. Some ciliates and their bacterial symbionts have become friends for life, as researchers from the Max Planck Institute for Marine Microbiology in Bremen demonstrated by comparing a group of these single-celled ciliates and their bacterial partners from the Caribbean and the Mediterranean Seas. The bacteria provide their ciliate hosts with nutrition by oxidizing sulfur. Surprisingly, they found that this partnership originated once, from a single ciliate ancestor and a single bacterial ancestor, although a whole ocean separates the sampling sites. Several Kentrophoros ciliates from the Mediterranean Sea under the microscope. The sulfur in the bacteria reflects the  light and makes them appear white. One of the objects is not a ciliate, but an intruder, a multicellular flatworm.  Each ciliate is up to three Millimeter in length [Credit: MPI f. for Marine Microbiology/O. Jackle] Ciliates are minute, single...

The copepod species Calanus finmarchicus schedules its day using a genetic clock that works independently of external stimuli. The clock shapes the copepod's metabolic rhythms and daily vertical migration. This, in turn, has an enormous influence on the entire food web in the North Atlantic, where Calanus finmarchicus is a central plankton species. Wherever the high-calorie copepod is found determines where its predator species are. The results of the study will be published in the journal Current Biology . Calanus finmarchicus is a central plankton species with an enormous influence on the entire food web  in the North Atlantic [Credit: Alfred Wegener Institute] The world's oceans are home to a massive vertical migration. At dusk, countless plankton species, like copepods and krill, rise to the surface, where they gorge themselves on single-celled algae that can only thrive where there is sufficient sunlight. The cover of night offers the plankton protection from predators lik...

In the very earliest stages of life, mammalian cells multiply and form the embryo. New research from the University of Copenhagen suggests that this process might be much simpler than we thought. The development of the embryo can be cut down to the cell’s ability to count their neighbouring cells. 4.5 days after fertilization the early mammalian embryo consists of approximately 100 cells. At this stage the cells  form a structure consisting of a fluid-filled cavity and three different cell types. The yellow cells develop into  the placenta, the red cells become the yolk sac and the green cells develop into the embryo proper  [Credit: University of Copenhagen] One of the things that make human beings and other mammals unique in the animal kingdom is our cells’ ability to remember how to make an embryo. Development is the process by which a single cell, a fertilised egg, makes a complex body with head, tail, arms and legs. Mammalian cells can begin this process without any ...

New biological information gleaned from the red vizcacha rat, a native species of Argentina, demonstrates how genomes can rapidly change in size. Red vizcacha rat, a rare species found in Argentina [Credit: McMaster University] Researchers from McMaster University set out to study this particular species because its genome, or its complete set of DNA, is the largest of all mammals, and appears to have increased in size very rapidly. The rat's genome is roughly two-and-a-half times as large as the human genome, including 102 chromosomes versus 46 for humans, and is about twice as large as one of its closest relatives, the mountain vizcacha rat. The most recent common ancestor of these species existed only about five million years ago. "This genomic transformation is striking because it happened over a very short period of time in evolutionary terms," says Ben Evans, a biologist at McMaster and lead author of the new research published in the journal Genome Biology and Evol...

A  global team of researchers has published the first-ever Wild Emmer wheat genome sequence in Science magazine . Wild Emmer wheat is the original form of nearly all the domesticated wheat in the world, including durum (pasta) and bread wheat. Wild emmer is too low-yielding to be of use to farmers today, but it contains many attractive characteristics that are being used by plant breeders to improve wheat. Wild Emmer wheat [Credit: © Energin.R Technologies 2009 LTD] The study was led by Dr. Assaf Distelfeld of Tel Aviv University's School of Plant Sciences and Food Security and Institute for Cereal Crops Improvement, in collaboration with several dozen scientists from institutions around the world and an Israel-based company, NRGene, which developed the bioinformatics technology that accelerated the research. "This research is a synergistic partnership among public and private entities," said Dr. Daniel Chamovitz, Dean of TAU's George S. Wise Faculty of Life Sciences,...

A new study involving The University of Queensland, which might be useful for biomedical research, re-writes parts of the rulebook on how mammalian brains -- including our own -- could have evolved. Chart of 3D-reconstructed dissected brains and, where available, head outlines used in this study. Green/light red,  the two olfactory bulbs; orange/blue, cerebral hemispheres; dark green, midbrain; yellow, cerebellum;  cherry red, medulla [Credit: Dr. Vera Weisbecker] It includes the possibility that distinctive dominance of our own cerebral hemispheres is not, as previously suggested, just a side-effect that forces brains of a particular size to have particular proportions. Dr Vera Weisbecker of UQ's School of Biological Sciences said the study represented the first dataset comparing brain growth in different mammals, gathered through a novel method of non-invasive micro-CT (computed tomography) scanning which allowed the fast data acquisition of soft tissue growth in tiny mammal...

The evolution of plants has been punctuated by major innovations, none more striking among living plants than the flower. Flowering plants account for the vast majority of living plant diversity and include all major crops. All flowers share a history of genome duplication, which may have contributed to their spectacular diversity  [Credit: James Clark, University of Bristol] The discovery that all flowering plants underwent a doubling of their genome at some point during their evolution has led to speculation that this duplication event triggered the diversification of this spectacular lineage, but the timing of this event has remained difficult to pin down. Genome duplications provide a second copy of every single gene on which selection can act, potentially leading to new forms and greater diversity. This process leads to the formation of large families of genes - we can examine the history of duplication in gene families in the genomes of all major groups of plants and then loo...

A major effort is underway to conserve the last remaining 60 individual paintbrush lilies (Haemanthus pumilio) in the Duthie Nature Reserve in Stellenbosch, South Africa, as well as increase the population through micropropagation. Only 10-15 centimetres high, Haemanthus pumilio is one of the smallest paintbrush lilies. The plants usually flower during  March and April, before the leaves develop. This species prefers to flower after fire, when there is less competition  from other vegetation [Credit: Dr Gary Stafford] Martin Smit, curator of the Stellenbosch University Botanical Garden, says more than a thousand of the paintbrush lilies once grew in the Duthie reserve. But the reserve is now less than a third of its original size, and the lilies have all but disappeared from previously known locations including Wellington and Klapmuts. "The main reasons for its decline are the destruction of its original habitat (rhenosterveld) and invasives like Port Jackson (Acacia saligna)....

By analyzing the DNA of two prehistoric dogs from Germany, an international research team led by Krishna R. Veeramah, PhD, Assistant Professor of Ecology & Evolution in the College of Arts & Sciences at Stony Brook University, has determined that their genomes were the probable ancestors of modern European dogs. The finding, to be published in Nature Communications , suggests a single domestication event of modern dogs from a population of gray wolves that occurred between 20,000 and 40,000 years ago. The 5000 year old Late Neolithic CTC dog skull in the lab before it underwent whole genome sequencing  [Credit: Amelie Scheu] Dogs were the first animal to be domesticated by humans. The oldest dog fossils that can be clearly distinguished from wolves are from the region of what is now Germany from around 15,000 years ago. However, the archaeological record is ambiguous, with claims of ancient domesticated dog bones as far east as Siberia. Recent analysis of genetic da...

For three years, Tara Djokic, a Ph.D. student at the University of New South Wales Sydney, scoured the forbidding landscape of the Pilbara region of Western Australia looking for clues to how ancient microbes could have produced the abundant stromatolites that were discovered there in the 1970s. Conical stromatolite (view from the top) at the Trendall locality in the Pilbara  [Credit: © Government of Western Australia] Stromatolites are round, multilayered mineral structures that range from the size of golf balls to weather balloons and represent the oldest evidence that there were living organisms on Earth 3.5 billion years ago. Scientists who believed life began in the ocean thought these mineral formations had formed in shallow, salty seawater, just like living stromatolites in the World Heritage-listed area of Shark Bay, which is a two-day drive from the Pilbara. But what Djokic discovered amid the strangling heat and blood-red rocks of the region was evidence that ...