̽��ֱ�� of Cambridge - Peter Walsh

Gorillas found to live in 'complex' societies, suggesting deep roots of human social evolution

fpjl2 — Wed, 10 Jul 2019 05:24:40 +0000

Algorithms reveal “social tiers” in gorillas seen in only a few other species, such as dolphins and humans. Researchers suggest that some of these social bonds may be analogous to “old friendships” and “tribes” in humans.

Final biomedical trial on captive chimpanzees is first oral Ebola vaccine for saving wild apes

fpjl2 — Thu, 09 Mar 2017 12:06:41 +0000

̽��ֱ��results from the final biomedical research trial on captive chimpanzees for the foreseeable future have been published today in the journal Scientific Reports.

̽��ֱ��trial was of a vaccination for Ebola: the first orally administered vaccine for any disease developed specifically for the purpose of conserving wild apes.

In addition to poaching and forest loss, diseases such as Ebola and anthrax have devastated wild ape populations. Ebola alone is estimated to have killed one third of the world’s wild gorillas over the last three decades.

Now, new findings have shown an effective oral vaccine for Ebola in chimpanzees, and that the captive animals involved in the trial exhibited very few signs of stress as a result. Researchers say the work demonstrates a model that could be harnessed for other diseases and ape species in the wild.

However, after decades using chimpanzees to test vaccines destined for humans, changes in the law have seen enforced retirement of captive populations and the closing of chimpanzee research facilities in the US – the last developed country where biomedical testing on chimpanzees was legal.

In what researchers describe as a “horrible irony”, they say these reforms – a victory for long-standing campaigns by animal welfare groups – will ultimately prove detrimental to chimpanzees and gorillas in the wild, as any vaccination for wild animals must be tested in captivity first to ensure its safety.

Consequently, the promising new vaccine model may never progress to the point where it can be used to inoculate endangered wild apes, say the research team from the universities of Cambridge, UK, and Thomas Jefferson and Louisiana, US.

“In 2014 the world was gripped by fears of an Ebola virus pandemic. Yet few people realise that Ebola has already inflicted pandemic scale mortality on our closest relatives,” says lead researcher Dr Peter Walsh from the ̽��ֱ�� of Cambridge.

“African apes are also threatened by naturally occurring pathogens like anthrax, and the increasing overspill of human pathogens such as measles. A glimmer of hope lies in the fact that many of the disease threats are now vaccine preventable.

“We have developed a very promising tool for inoculating ape species against the myriad deadly diseases they face in the wild, but continued progress relies on access to a small number of captive animals.

“This may be the final vaccine trial on captive chimpanzees: a serious setback for efforts to protect our closest relatives from the pathogens that push them ever closer to extinction in the wild.”

Previous attempts to vaccinate wild apes have resorted to administering individual animals with hypodermic darts – a laborious task feasible for only a small number of apes habituated to human approach. By contrast, oral vaccines encased in appealingly edible baits could be distributed across wild ape territories to inoculate large numbers over longer periods.

Such an approach has already proved successful in other species: almost eliminating fox rabies (and the consequent need to cull foxes) across continental Europe.

̽��ֱ��latest study was carried out with ten chimpanzees in one of the last remaining chimpanzee research facilities in the US in New Iberia, Louisiana. Six received the oral vaccine, while four were injected as a control group.

All the animals displayed a robust immunity without side effects after 28 days – when the trial was terminated due to new Endangered Species Act regulations banning biomedical research on chimpanzees.

Throughout the trial, scientists closely monitored animal behaviour and physiology for signs of severe stress. Other than very minor weight loss (2% of body mass), they say that signs of trauma were “entirely absent”.

“Some pressure groups argue that all research on captive chimpanzees is tantamount to torture, not just because of procedures but also due to confinement,” says Walsh.

“Enclosures and animal care are now of a very high standard, with chimpanzees housed in large social spaces. ̽��ֱ��modest traces of stress we detected during our trial were akin to the values observed in college students anticipating exams.”

Captive chimpanzee trials are technically still legal in the US in instances that benefit the species. However, Walsh says that the limited funds available for conservation research makes it unviable for biomedical facilities to retain populations, while zoos and sanctuaries are either “ideologically opposed” or unwilling to risk any public backlash from testing.

Further work to enhance the vaccine, such as ensuring effectiveness after exposure to high tropical forest temperatures, may now never get done due to the closure of captive chimpanzee facilities.

“In an ideal world, there would be no need for captive chimpanzees,” says Walsh. “But this is not an ideal world. It is a world where diseases such as Ebola, along with rampant commercial poaching and habitat loss, are major contributors to rapidly declining wild ape populations.

“Oral vaccines offer a real opportunity to slow this decline. ̽��ֱ��major ethical debt we owe is not to a few captive animals, but to the survival of an entire species we are destroying in the wild: our closest relatives.”

Oral vaccine offers hope for ape species ravaged by Ebola and other diseases, as it can be widely dispersed to save more wild animals. However, scientists say recent law changes on captive chimpanzee testing may stop the conservation work in its tracks.

This may be the final vaccine trial on captive chimpanzees: a serious setback for efforts to protect our closest relatives from the pathogens that push them ever closer to extinction in the wild

Peter Walsh

Matthias Schnell

One of the captive chimpanzees in the research trial receiving the oral Ebola vaccination

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Was the dawn of man among trees in the cradle of disease?

fpjl2 — Thu, 04 Jul 2013 08:22:23 +0000

When the family of Albert Perry - a recently deceased African-American man from South Carolina - sent a sample of his DNA to be tested by a genealogy website, they weren’t expecting to rewrite the history of mankind. They were probably just a bit curious.

But Perry’s DNA contained a Y chromosome not seen before, one which potentially reveals that the last common male ancestor in the paternal line of humanity is almost twice as old as previously thought – some 338,000 years, even though the oldest fossil of man is only 195,000 years old.

̽��ֱ��DNA was traced back to the Mbo ethnic group in central Africa, based primarily in South West Cameroon, suggesting that the dawn of modern man took place deep in the inhospitable forests of this region rather than the savannahs of East Africa, the area that conventional science has – until now – located as the site of the first homo sapiens.

This Friday, a student-run conference hosted by Cambridge’s Biological Anthropology Division will focus on this groundbreaking research, published earlier this year by a team from the ̽��ֱ�� of Arizona and UCL, to ask some of the major questions it raises: How might this change our understanding of human evolution? Does the forest still influence who we are today?

Relocating Origin will feature experts from Cambridge and elsewhere, including one of the UCL scientists who conducted the original research, Professor Mark Thomas, and will be available to watch through a live webcast.

“This is a hugely exciting time for human origin studies. If these early findings are proved correct, the current narratives of the beginning of our species have been predicated on a different location and a different time!” says Katie Fitzpatrick, a PhD candidate in the Department and one of the conference organisers.

“ ̽��ֱ��hot, humid forests work against fossil preservation as they just decay in such climates – unlike arid regions that have been the focus of early human research so far. However, the evidence may still be in the rainforests but we haven’t been looking”.

By asking ‘What if Adam lived in the forest?’ scientists will explore the implications not just for genetics but human culture, technology and society.

̽��ֱ��impact of a forest home on the social structure of the first homo sapiens will be examined by the Division’s Dr Peter Walsh, who researches social networks in primate ecology. A major theme of the conference will be what’s known as Behavioural Immune System hypothesis – the idea that social behaviour is an intrinsic part of the immune system, and infectious disease transmission can dictate social contact, especially in the heart of Africa.

“ ̽��ֱ��forest region of central Africa is the disease epicentre of the universe! HIV from chimps, bats carrying rabies, Ebola, SARS, insect vectors carrying malaria and parasitic diseases like river blindness and elephantitis, loads of fecal-oral diseases… It’s described as ‘pathogen rain’,” says Walsh.

“You live in a big group with lots of social interaction, and one of you gets Ebola – everybody dies. So it doesn’t make evolutionary sense in such places”.

Walsh suggests that the region’s ‘pathogen rain’ could have stunted early human development, as limited interactions due to fear of disease meant that ideas and innovations were unable to spread and build, leaving our first ancestors languishing in the forest for thousands of years.

“In disease hotbeds, people have much stronger group identification, which makes them much more hostile – part of the behavioural immune system. You see the same in gorillas.”

One possible theory Walsh will discuss is that, instead of a “key innovation” – such as walking upright or fire - triggering human development, just getting out of the disease-riddled forests could have allowed for much greater social interaction that sparked a “cascade of technological innovation”.

And it is a much more recent human innovation opening up these possibilities. We now live in the age of ‘big data’. ̽��ֱ��access to unprecedented reams of digital information is transforming almost every area of academic research in tandem with society in general: “This capacity to have genetic samples from vast numbers of people is giving us a whole new view of why we are the way we are, and this is only the start,” says Walsh.

While the evolutionary scientists stress that much more research needs to be done in the region, which presents all manner of challenges from unfavourable climates for fossilized evidence to political instability, the conference will be the first to look at the emergence of this brand new direction in the field, and how it can be taken “from speculation to science”.

“Certain methodologies need to be nailed down, which will take a few years, but this avenue of investigation could lead to the reassessment of a huge range of thinking around fire, meat-eating, bipedalism, locomotion – when and how these things happened are all potentially up for discussion,” adds Walsh.

“What we want to ask is how this might change things, to get people to start thinking about the possibility that the last fifty years of research has been mistaken in its assumptions about where we came from.”

For a full list of speakers and topics, and a link to the live webcast of the conference, go to http://relocatingorigin.soc.srcf.net/

Inset image: Dr Peter Walsh

A student-led conference to be webcast live will ask, in light of recent research, whether the story of human origin is radically different from established thinking, and what that might mean for everything from genetics to the birth of culture.

̽��ֱ��forest region of central Africa is the disease epicentre of the universe… It’s described as ‘pathogen rain’

Peter Walsh

Peter Walsh. Banner image credit Strollerdos

Forest region of South West Cameroon

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