Archaeology News Online

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 ...

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...

New research published in Nature Climate Change has revealed how strengthening winds on the opposite side of Antarctica, up to 6000kms away, drive the high rate of ice melt along the West Antarctic Peninsula. The path of the Kelvin waves that interact with the Antarctic Circumpolar Current and push warmer waters under  the ice shelves of the West Antarctic Peninsula. These waves are generated by strengthening winds,  6000km away, on the opposite side of the Antarctic [Credit: Ryan Holmes/NCI] Researchers from the ARC Centre of Excellence for Climate System Science found that the winds in East Antarctica can generate sea-level disturbances that propagate around the continent at almost 700 kilometers per hour via a type of ocean wave known as a Kelvin wave. When these waves encounter the steep underwater topography off the West Antarctic Peninsula they push warmer water towards the large ice shelves along the shoreline. The warm Antarctic Circumpolar Current passes quite close ...

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...

Climate change leads to loss of biodiversity worldwide. However, ecosystems with a higher biodiversity in the first place might be less affected a new study in Science Advances reports. An international research team found that when they experimentally warmed meadows, the diversity of nematode worms living in the soil went down in monocultures, whereas the opposite was true for meadows with many different herbaceous plant species. A predatory female nematode of the genus Clarkus under the microscope [Credit: Marcel Ciobanu] The last month was recorded as the warmest June ever in many parts of the world. Last year, 2016, was the warmest year in the modern temperature record. Our planet is constantly heating up. This poses direct threats to humans, like extreme weather events and global sea-level rise, but scientists are concerned that it may also affect our well-being indirectly via changes in biodiversity. The variety of life, from plants and animals to microorganisms, is the basis of...

Populations of endangered species reach a critical point in their life where they either survive or evolve towards extinction. Therefore, efforts to predict and even prevent the extinction of biological species require a thorough understanding of the underlying mechanisms. The Siberian tiger is an Endangered (EN) tiger subspecies. Three tiger subspecies are already extinct  [Credit: WikiCommons] In a new study published in EPJ B , Hatem Barghathi and colleagues from Missouri University of Science and Technology, USA, have investigated how environmental disturbance at random times could cause strong fluctuations in the number of individuals in biological populations. This, in turn, makes extinction easier, even for large populations. They found that environmental disorder can lead to a period of slow population increase interrupted by sudden population collapses. These findings also have implications for solving the opposite problem when attempting to predict, control and eradicate ...

The Greenland ice sheet is often seen as a pristine environment, but new research has revealed that may not be the case. The Greenland ice sheet is often seen as a pristine environment, but new research has revealed that may not be the case  [Credit: IOP Publishing] A Danish-led study, published today in the journal Environmental Research Letters , examined how microbes from the ice sheet have the potential to resist and degrade globally-emitted contaminants such as mercury, lead, PAH and PCB. Dr Aviaja Hauptmann, from the University of Greenland, led the research. She said: "Globally emitted contaminants accumulate in the Arctic and are stored in the frozen environments of the cryosphere, essentially meaning they have become reservoirs of toxic chemicals. "Our understanding of how biological processes interact with contamination in the Arctic is limited, which is why we hope our study represents a large step forward in the understanding and solving of this problem." The...

No bells tolled when the last Catarina pupfish on Earth died. Newspapers didn't carry the story when the Christmas Island pipistrelle vanished forever. Tropical forest logging has contributed to population declines in many animals,  including the Bornean gibbon, known for its whooping call  [Credit: Gerardo Ceballos] Two vertebrate species go extinct every year on average, but few people notice, perhaps because the rate seems relatively slow -- not a clear and present threat to the natural systems we depend on. This view overlooks trends of extreme decline in animal populations, which tell a more dire story with cascading consequences, according to a new study that provides the first global evaluation of these population trends. "This is the case of a biological annihilation occurring globally, even if the species these populations belong to are still present somewhere on Earth," said co-author Rodolfo Dirzo, a professor of biology. Mapping loss A 2015 study co-authored b...

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 ...

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...

New research published in Nature Climate Change has revealed how strengthening winds on the opposite side of Antarctica, up to 6000kms away, drive the high rate of ice melt along the West Antarctic Peninsula. The path of the Kelvin waves that interact with the Antarctic Circumpolar Current and push warmer waters under  the ice shelves of the West Antarctic Peninsula. These waves are generated by strengthening winds,  6000km away, on the opposite side of the Antarctic [Credit: Ryan Holmes/NCI] Researchers from the ARC Centre of Excellence for Climate System Science found that the winds in East Antarctica can generate sea-level disturbances that propagate around the continent at almost 700 kilometers per hour via a type of ocean wave known as a Kelvin wave. When these waves encounter the steep underwater topography off the West Antarctic Peninsula they push warmer water towards the large ice shelves along the shoreline. The warm Antarctic Circumpolar Current passes quite close ...

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...

Climate change leads to loss of biodiversity worldwide. However, ecosystems with a higher biodiversity in the first place might be less affected a new study in Science Advances reports. An international research team found that when they experimentally warmed meadows, the diversity of nematode worms living in the soil went down in monocultures, whereas the opposite was true for meadows with many different herbaceous plant species. A predatory female nematode of the genus Clarkus under the microscope [Credit: Marcel Ciobanu] The last month was recorded as the warmest June ever in many parts of the world. Last year, 2016, was the warmest year in the modern temperature record. Our planet is constantly heating up. This poses direct threats to humans, like extreme weather events and global sea-level rise, but scientists are concerned that it may also affect our well-being indirectly via changes in biodiversity. The variety of life, from plants and animals to microorganisms, is the basis of...

Populations of endangered species reach a critical point in their life where they either survive or evolve towards extinction. Therefore, efforts to predict and even prevent the extinction of biological species require a thorough understanding of the underlying mechanisms. The Siberian tiger is an Endangered (EN) tiger subspecies. Three tiger subspecies are already extinct  [Credit: WikiCommons] In a new study published in EPJ B , Hatem Barghathi and colleagues from Missouri University of Science and Technology, USA, have investigated how environmental disturbance at random times could cause strong fluctuations in the number of individuals in biological populations. This, in turn, makes extinction easier, even for large populations. They found that environmental disorder can lead to a period of slow population increase interrupted by sudden population collapses. These findings also have implications for solving the opposite problem when attempting to predict, control and eradicate ...