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...

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...

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...

Throughout the history of life, new groups of species have flourished at the expense of earlier ones and global biodiversity has varied dramatically over geologic time. A new study led by the University of Turku, Finland, shows that completely different factors regulate the rise and fall of species. Tree ferns still occupy the tropical moist forests in Australia, even though  they shared their 'golden age' with dinosaurs  [Credit: Samuli Lehtonen] "Previously, the debate has been about whether biodiversity is regulated mainly by the interaction between species or the external environment," explains researcher and leader of the study Samuli Lehtonen from the Biodiversity Unit of the University of Turku. In order to test these competing views, Lehtonen compiled a group of top researchers from Finland, Sweden, Switzerland and the United States. The researchers focused on the diversity of ferns and the factors that influenced it during the past 400 million years. Ferns ha...

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)....

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...

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...

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...