Archaeology News Online

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 ...

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...

The orangutan population on the island of Borneo has shrunk by a quarter in the last decade, researchers said Friday, urging a rethink of strategies to protect the critically-endangered great ape. Borneo's orangutans are under threat from farming, climate change, and being hunted for food  [Credit: AFP/Bay Ismoyo] The first-ever analysis of long-term orangutan population trends revealed a worrying decline, they said. An international team of researchers used a combination of helicopter and ground surveys, interviews with local communities, and modelling techniques to draw a picture of change over the past ten years. Previous counts have largely relied on estimations based on ground and aerial surveys of orangutan nests. Some suggested that Bornean orangutan numbers were in fact increasing. The new findings, the team said in a statement, are "a wake-up call for the orangutan conservation community and the Indonesian and Malaysian governments who have committed to saving the spe...

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)....

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 ...