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 ...

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...

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...

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 ...

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...

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...

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...

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...

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 ...