Without humans, the whole world could look like Serengeti

The fact that the greatest diversity of large mammals is found in Africa reflects past human activities -- and not climatic or other environmental constraints. This is determined in a new study, which presents what the world map of mammals would look like if modern man (Homo sapiens) had never existed.

The natural diversity of large mammals is shown as it would appear without the impact
 of modern man (Homo sapiens). The figure shows the variation in the number
 of large mammals (45 kg or larger) that would have occurred per 100 x 100 
kilometer grid cell. The numbers on the scale indicate the 
number of species [Credit: Soren Faurby]

In a world without humans, most of northern Europe would probably now be home to not only wolves, Eurasian elk (moose) and bears, but also animals such as elephants and rhinoceroses.

This is demonstrated in a new study conducted by researchers from Aarhus University, Denmark. In a previous analysis, they have shown that the mass extinction of large mammals during the Last Ice Age and in subsequent millennia (the late-Quaternary megafauna extinction) is largely explainable from the expansion of modern man (Homo sapiens) across the world. In this follow-up study, they investigate what the natural worldwide diversity patterns of mammals would be like in the absence of past and present human impacts, based on estimates of the natural distribution of each species according to its ecology, biogeography and the current natural environmental template. They provide the first estimate of how the mammal diversity world map would have appeared without the impact of modern man.

"Northern Europe is far from the only place in which humans have reduced the diversity of mammals -- it's a worldwide phenomenon. And, in most places, there's a very large deficit in mammal diversity relative to what it would naturally have been," says Professor Jens-Christian Svenning, Department of Bioscience, Aarhus University, who is one of the researchers behind the study.

Africa is the last refuge

The current world map of mammal diversity shows that Africa is virtually the only place with a high diversity of large mammals. However, the world map constructed by the researchers of the natural diversity of large mammals shows far greater distribution of high large-mammal diversity across most of the world, with particularly high levels in North and South America, areas that are currently relatively poor in large mammals.

The current diversity of large mammals is shown. It can clearly be seen that large
 numbers of species virtually only occurs in Africa, and that there are generally
 far fewer species throughout the world than there could have been
[Credit: Soren Faurby]

"Most safaris today take place in Africa, but under natural circumstances, as many or even more large animals would no doubt have existed in other places, e.g., notably parts of the New World such as Texas and neighboring areas and the region around northern Argentina-Southern Brazil. The reason that many safaris target Africa is not because the continent is naturally abnormally rich in species of mammals. Instead it reflects that it's one of the only places where human activities have not yet wiped out most of the large animals," says Postdoctoral Fellow Soren Faurby, Department of Bioscience, Aarhus University, who is the lead author on the study.

The existence of Africa's many species of mammals is thus not due to an optimal climate and environment, but rather because it is the only place where they have not yet been eradicated by humans. The underlying reason includes evolutionary adaptation of large mammals to humans as well as greater pest pressure on human populations in long-inhabited Africa in the past.

Better understanding helps nature preservation

The study's openly accessible data set of natural range maps for all late-Quatenary mammals provides researchers with the first opportunity to analyse the natural patterns in the species diversity and composition of mammals worldwide. Hereby, it can be used to provide a better understanding of the natural factors that determine the biodiversity in a specific area.

Today, there is a particularly large number of mammal species in mountainous areas. This is often interpreted as a consequence of environmental variation, where different species have evolved in deep valleys and high mountains. According to the new study, however, this trend is much weaker when the natural patterns are considered.

"The current high level of biodiversity in mountainous areas is partly due to the fact that the mountains have acted as a refuge for species in relation to hunting and habitat destruction, rather than being a purely natural pattern. An example in Europe is the brown bear, which now virtually only live in mountainous regions because it has been exterminated from the more accessible and most often more densely populated lowland areas," explains Soren Faurby.

Hereby, this new study can provide an important base-line for nature restoration and conservation.

The study has been published in the scientific journal Diversity and Distributions.

Source: Aarhus University [August 20, 2015]

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The unique ecology of human predators

Are humans unsustainable 'super predators'? Want to see what science now calls the world's "super predator"? Look in the mirror.

Big game hunter Gary Kock and 'prize' 
[Credit: The Greanville Post]

Research published today in the journal Science by a team led by Dr. Chris Darimont, the Hakai-Raincoast professor of geography at the University of Victoria, reveals new insight behind widespread wildlife extinctions, shrinking fish sizes and disruptions to global food chains.

"These are extreme outcomes that non-human predators seldom impose," Darimont's team writes in the article titled "The Unique Ecology of Human Predators."

A coastal wolf is hunting salmon in British Columbia, Canada 
[Credit: Guillaume Mazille]

"Our wickedly efficient killing technology, global economic systems and resource management that prioritize short-term benefits to humanity have given rise to the human super predator," says Darimont, also science director for the Raincoast Conservation Foundation. "Our impacts are as extreme as our behaviour and the planet bears the burden of our predatory dominance."

The team's global analysis indicates that humans typically exploit adult fish populations at 14 times the rate of marine predators. Humans hunt and kill large land carnivores such as bears, wolves and lions at nine times the rate that these predatory animals kill each other in the wild.

Wildlife under pressure. Darimont et al. show that the rates at which humans exploit 
land mammals and marine fish vastly exceeds the impacts of other predators. 
Marine fish experience “fishing through marine food webs,” with different trophic 
groups similarly affected. In contrast, on land top predators are exploited at 
much higher rates than are herbivores [Credit: P. Huey/Science]

Humanity also departs fundamentally from predation in nature by targeting adult quarry. "Whereas predators primarily target the juveniles or 'reproductive interest' of populations, humans draw down the 'reproductive capital' by exploiting adult prey," says co-author Dr. Tom Reimchen, biology professor at UVic. Reimchen originally formulated these ideas during long-term research on freshwater fish and their predators at a remote lake on Haida Gwaii, an archipelago on the northern coast of British Columbia.

Source: University of Victoria [August 20, 2015]

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The Sumatran rhino is extinct in the wild in Malaysia

Leading scientists and experts in the field of rhino conservation state in a new paper that it is safe to consider the Sumatran rhinoceros extinct in the wild in Malaysia. The survival of the Sumatran rhino now depends on the 100 or fewer remaining individuals in the wild in Indonesia and the nine rhinos in captivity.

Sumatran rhino [Credit: Rasmus Gren Havmoller]

Despite intensive survey efforts, there have been no signs of the wild Sumatran rhinoceros (Dicerorhinus sumatrensis) in Malaysia since 2007, apart from two females that were captured for breeding purposes in 2011 and 2014. Scientists now consider the species extinct in the wild in Malaysia. The experts urge conservation efforts in Indonesia to pick up the pace.

The conclusions are published online in Oryx, the International Journal of Conservation, led by the Center for Macroecology, Evolution and Climate at the University of Copenhagen. Partners include WWF, the International Rhino Foundation and IUCN, the International Union for Conservation of Nature, which is in charge of the global Red List of Threatened Species.

Surviving rhinos are too far apart

"It is vital for the survival of the species that all remaining Sumatran rhinos are viewed as a metapopulation, meaning that all are managed in a single program across national and international borders in order to maximize overall birth rate. This includes the individuals currently held in captivity," says lead author and PhD student Rasmus Gren Havmoller from the Center for Macroecology, Evolution and Climate.

The experts point to the creation of intensive management zones as a solution; areas with increased protection against poaching, where individual rhinos can be relocated to, in order to increase the number of potential and suitable mating partners.

Historically ranging across most of South-east Asia, the Sumatran rhino is now only found in the wild in Indonesia. Here, less than 100 individuals in total are estimated to live in three separate populations, one of which has seen a critical decline in distribution range of 70 % over the last decade. This trend echoes how the Sumatran rhino population dropped from around 500 to extinction between 1980 and 2005 in Sumatra's largest protected area, the enormous 1,379,100 hectare Kerinci Sebelat National Park.

Apart from the wild populations, nine Sumatran rhinos are in captivity, with one in Cincinnati Zoo in U.S.A (soon to be moved to Indonesia), three held at facilities in Sabah, Malaysia for attempts to produce embryos by in vitro fertilization, and five in the Sumatran Rhino Sanctuary in Sumatra, Indonesia.

Two year old conservation strategy awaits political will

The intensive management zones as well as the single population strategy are two of four key actions identified back in April 2013 at the Sumatran Rhino Crisis Summit in Singapore and agreed upon that same year by the Indonesian government in the Bandar Lampung Declaration.

"The tiger in India was saved from extinction due to the direct intervention of Mrs. Gandhi, the then prime minister, who set up Project Tiger. A similar high level intervention by President Joko Widodo of Indonesia could help pull the Sumatran rhinos back from the brink" says Christy Williams, co-author and coordinator of the WWF Asian and Rhino and Elephant Action Strategy.

Widodo Ramono, co-author and Director of the Rhino Foundation of Indonesia (YABI) elaborates: "Serious effort by the government of Indonesia should be put to strengthen rhino protection by creating Intensive Protection Zone (IPZ), intensive survey of the current known habitats, habitat management, captive breeding, and mobilizing national resources and support from related local governments and other stakeholders."

The global conservation strategy also included the continued development of Rhino Protection Units at sites with remaining breeding populations. While this has been achieved, the authors highlight a need for strengthening the units against poaching efforts, especially in northern Sumatra. With a high demand for rhinoceros horns in black markets in Asia, poaching continues to be a significant threat to the species.

Finally, captive breeding was included in 2013 as one of the key conservation actions, but the necessary reproductive technology may still take years to develop, during which time we may lose the Sumatran rhino in the wild, says the authors.

Source: Natural History Museum of Denmark [August 20, 2015]

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Apes may be closer to speaking than many scientists think

Koko the gorilla is best known for a lifelong study to teach her a silent form of communication, American Sign Language. But some of the simple sounds she has learned may change the perception that humans are the only primates with the capacity for speech.

Meet Koko, Gorilla Spokesperson [Credit: The Gorilla Foundation]

In 2010, Marcus Perlman started research work at The Gorilla Foundation, where Koko has spent more than 40 years living immersed with humans -- interacting for many hours each day with psychologist Penny Patterson and biologist Ron Cohn.

"I went there with the idea of studying Koko's gestures, but as I got into watching videos of her, I saw her performing all these amazing vocal behaviors," says Perlman, now a postdoctoral researcher in the lab of University of Wisconsin-Madison psychology Professor Gary Lupyan.

The vocal and breathing behaviors Koko had developed were not necessarily supposed to be possible.

"Decades ago, in the 1930s and '40s, a couple of husband-and-wife teams of psychologists tried to raise chimpanzees as much as possible like human children and teach them to speak. Their efforts were deemed a total failure," Perlman says. "Since then, there is an idea that apes are not able to voluntarily control their vocalizations or even their breathing."

Instead, the thinking went, the calls apes make pop out almost reflexively in response to their environment -- the appearance of a dangerous snake, for example.

And the particular vocal repertoire of each ape species was thought to be fixed. They didn't really have the ability to learn new vocal and breathing-related behaviors.

These limits fit a theory on the evolution of language, that the human ability to speak is entirely unique among the nonhuman primate species still around today.

"This idea says there's nothing that apes can do that is remotely similar to speech," Perlman says. "And, therefore, speech essentially evolved -- completely new -- along the human line since our last common ancestor with chimpanzees."

However, in a study published online in July in the journal Animal Cognition, Perlman and collaborator Nathaniel Clark of the University of California, Santa Cruz, sifted 71 hours of video of Koko interacting with Patterson and Cohn and others, and found repeated examples of Koko performing nine different, voluntary behaviors that required control over her vocalization and breathing. These were learned behaviors, not part of the typical gorilla repertoire.

Among other things, Perlman and Clark watched Koko blow a raspberry (or blow into her hand) when she wanted a treat, blow her nose into a tissue, play wind instruments, huff moisture onto a pair of glasses before wiping them with a cloth and mimic phone conversations by chattering wordlessly into a telephone cradled between her ear and the crook of an elbow.

"She doesn't produce a pretty, periodic sound when she performs these behaviors, like we do when we speak," Perlman says. "But she can control her larynx enough to produce a controlled grunting sound."

Koko can also cough on command -- not particularly groundbreaking human behavior, but impressive for a gorilla because it requires her to close off her larynx.

"The motivation for the behaviors varies," Perlman says. "She often looks like she plays her wind instruments for her own amusement, but she tends to do the cough at the request of Penny and Ron."

These behaviors are all learned, Perlman figures, and the result of living with humans since Koko was just six months old.

"Presumably, she is no more gifted than other gorillas," he says. "The difference is just her environmental circumstances. You obviously don't see things like this in wild populations."

This suggests that some of the evolutionary groundwork for the human ability to speak was in place at least by the time of our last common ancestor with gorillas, estimated to be around 10 million years ago.

"Koko bridges a gap," Perlman says. "She shows the potential under the right environmental conditions for apes to develop quite a bit of flexible control over their vocal tract. It's not as fine as human control, but it is certainly control."

Orangutans have also demonstrated some impressive vocal and breathing-related behavior, according to Perlman, indicating the whole great ape family may share the abilities Koko has learned to tap.

Author: Chris Barncard | Source: University of Wisconsin-Madison [August 14, 2015]

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Rhino horns, elephant tusks seized in Vietnam

Police in Vietnam have seized more than 700 kilograms (1,500 pounds) of rhino horns and elephant tusks believed to have originated from Mozambique, state media said Friday.

Authorities confiscated the tusks and horns hidden in two containers on the 
King Prian ship when it docked at Tien Sa port [Credit: VOV]

The haul of prized animal parts was discovered hidden in two containers on board a ship carrying ground stones at the central port of Da Nang on Thursday, Tuoi Tre newspaper said.

"The elephant tusks weighed 593 kilograms and the rhino horn chunks weighed 142 kilograms," the report said, adding that the illegal shipment had come via Malaysia.

The final destination of the shipment was not reported but the boat was scheduled to stop in on Vietnam's northern Hai Phong port.

Communist Vietnam has long been accused of being one of the world's worst countries for trade in endangered species.

There have been a number of campaigns to warn Vietnamese not to use products from endangered animals but they have had little success.

Demand for rhino horn remains high with people mistakenly believing it can cure anything from cancer to hangovers despite an absolute dearth of scientific evidence.

Horns are made from keratin, the same substance that makes up finger nails and hair in humans.

Tusks and other body parts of elephants are prized for decoration, as talismans, and for use in traditional medicine.

The rhino horn trade was banned globally by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in 1977.

But the trade has flourished in recent years, particularly thanks to demand from Vietnam and China with devastating results for Africa's rhino populations.

There are around just 5,000 black rhinos left on the planet and an estimated 20,000 white rhinos, mostly in southern Africa.

In 2011, the western black rhinoceros, a subspecies last seen in Cameroon, was declared extinct.

Source: AFP [August 14, 2015]

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