A giant Galapagos tortoise believed extinct for 150 years probably still exists, say scientists.
Chelonoidis elephantopus lived on the island of Floreana, and was heavily hunted, especially by whalers who visited the Galapagos to re-stock.
A Yale University team found hybrid tortoises on another island, Isabela, that appear to have C. elephantopus as one of their parents.
Some hybrids are only 15 years old, so their parents are likely to be alive.
The different shapes of the giant tortoises on the various Galapagos islands was one of the findings that led Charles Darwin to develop the theory of evolution through natural selection.
The animals are thought to have colonised the archipelago through floating from the shores of South America.
Colonies on each island remained relatively isolated from each other, and so evolved in subtly different directions.
C. elephantopus is especially notable for its saddleback-shaped shell, whereas species on neighbouring islands sported a dome-like carapace.
Three years ago, the Yale team reported finding some evidence of hybrids around Volcano Wolf at the northern end of Isabela Island, in amongst the native population of Chelonoidis becki.
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If you do some calculations you realise that there have to be a few elephantopus around to father these animals ”

Dr Gisella CacconeYale University
They speculated that through careful cross-breeding, it might be possible to re-create the extinct lineage - a process likely to take many generations.
Now, in the journal Current Biology, they report that this might not be necessary. A further expedition to Volcano Wolf found 84 tortoises that appear, from genetic samples, to have a pure-bred C. elephantopus as a parent.
Thirty of these are less than 15 years old; so the chances of the pure-blood parents still being alive are high, given that they can live to over 100 years old.
"Around Volcano Wolf, it was a mystery - you could find domed shells, you could find saddlebacks, and anything in between," recounted Gisella Caccone, senior scientist on the new study.

"And basically by looking at the genetic fingerprint of the hybrids, if you do some calculations you realise that there have to be a few elephantopus around to father these animals.
"To justify the amount of genetic diversity in the hybrids, there should be something like 38."
This number appears to include both males and females, given that some of the hybrids carry C. elephantopus mitochondrial DNA, which animals inherit exclusively from their mothers.
The theory is that some of the tortoises were probably taken by whaling ships that sailed from Floreana via the relatively remote Volcano Wolf en route to multi-year cruises in the Pacific looking for sperm whales.
Some of the giants made it to shore on Isabela, somehow, and established a presence.
The tortoises made an ideal food stock for whaling ships, as they can go without food for months and provided a source of fresh meat whenever the captain decided to kill them.
Needles, haystacks
The giant tortoises are so large, growing to nearly half a tonne, that you might think the elusive C. elephantopus would be easy to find.
The reality is rather different, according to Dr Caccone.
"The landscape on Volcano Wolf is hard, the vegetation thick with lots of bushes and nooks, and the carapaces are translucent so you need a trained eye to see the shininess of the shell," she told BBC News.
"The thing that struck us is that no-one knows what the population is on Volcano Wolf. We took 40 people [on our last expedition], and we had to stop collecting basically when we finished our supplies."
That trip took samples from over 1,600 individuals - which could be a small fraction of the population, indicating just how big a role the giant tortoises play in the ecosystem of the islands.
The Yale team now plans to discuss with Galapagos authorities whether to mount further exploratory expeditions, or whether to press ahead with a captive breeding programme.

A giant Galapagos tortoise believed extinct for 150 years probably still exists, say scientists.

Chelonoidis elephantopus lived on the island of Floreana, and was heavily hunted, especially by whalers who visited the Galapagos to re-stock.

A Yale University team found hybrid tortoises on another island, Isabela, that appear to have C. elephantopus as one of their parents.

Some hybrids are only 15 years old, so their parents are likely to be alive.

The different shapes of the giant tortoises on the various Galapagos islands was one of the findings that led Charles Darwin to develop the theory of evolution through natural selection.

The animals are thought to have colonised the archipelago through floating from the shores of South America.

Colonies on each island remained relatively isolated from each other, and so evolved in subtly different directions.

C. elephantopus is especially notable for its saddleback-shaped shell, whereas species on neighbouring islands sported a dome-like carapace.

Three years ago, the Yale team reported finding some evidence of hybrids around Volcano Wolf at the northern end of Isabela Island, in amongst the native population of Chelonoidis becki.

Start Quote

If you do some calculations you realise that there have to be a few elephantopus around to father these animals ”

Dr Gisella CacconeYale University

They speculated that through careful cross-breeding, it might be possible to re-create the extinct lineage - a process likely to take many generations.

Now, in the journal Current Biology, they report that this might not be necessary. A further expedition to Volcano Wolf found 84 tortoises that appear, from genetic samples, to have a pure-bred C. elephantopus as a parent.

Thirty of these are less than 15 years old; so the chances of the pure-blood parents still being alive are high, given that they can live to over 100 years old.

"Around Volcano Wolf, it was a mystery - you could find domed shells, you could find saddlebacks, and anything in between," recounted Gisella Caccone, senior scientist on the new study.

Map

"And basically by looking at the genetic fingerprint of the hybrids, if you do some calculations you realise that there have to be a few elephantopus around to father these animals.

"To justify the amount of genetic diversity in the hybrids, there should be something like 38."

This number appears to include both males and females, given that some of the hybrids carry C. elephantopus mitochondrial DNA, which animals inherit exclusively from their mothers.

The theory is that some of the tortoises were probably taken by whaling ships that sailed from Floreana via the relatively remote Volcano Wolf en route to multi-year cruises in the Pacific looking for sperm whales.

Some of the giants made it to shore on Isabela, somehow, and established a presence.

The tortoises made an ideal food stock for whaling ships, as they can go without food for months and provided a source of fresh meat whenever the captain decided to kill them.

Needles, haystacks

The giant tortoises are so large, growing to nearly half a tonne, that you might think the elusive C. elephantopus would be easy to find.

The reality is rather different, according to Dr Caccone.

"The landscape on Volcano Wolf is hard, the vegetation thick with lots of bushes and nooks, and the carapaces are translucent so you need a trained eye to see the shininess of the shell," she told BBC News.

"The thing that struck us is that no-one knows what the population is on Volcano Wolf. We took 40 people [on our last expedition], and we had to stop collecting basically when we finished our supplies."

That trip took samples from over 1,600 individuals - which could be a small fraction of the population, indicating just how big a role the giant tortoises play in the ecosystem of the islands.

The Yale team now plans to discuss with Galapagos authorities whether to mount further exploratory expeditions, or whether to press ahead with a captive breeding programme.

sexyactionplanet:

cameratrap:

Greater Anglehead (Gonocephalus grandis) in a Riverine forest in Malaysia

A fantastic new blog from a field biologist who photographs unique wildlife from his travels around the world. I have said before that I think nature photography is a great tool in conservation so I give this blog two thumbs up. Especially since many of these weird and wonderful creatures are from highly threatened ecosystems. 

sexyactionplanet:

cameratrap:

Greater Anglehead (Gonocephalus grandis) in a Riverine forest in Malaysia

A fantastic new blog from a field biologist who photographs unique wildlife from his travels around the world. I have said before that I think nature photography is a great tool in conservation so I give this blog two thumbs up. Especially since many of these weird and wonderful creatures are from highly threatened ecosystems. 


Click Me to help save Temengor, Belum rainforest
In April 2006, MNS (BirdLife in Malaysia) launched a campaign to save the Belum Temengor Forest Complex. The campaign aims to educate the public about the issues involved and to encourage the State and Federal governments to protect this critical area. Ideally, this would entail an end to all logging, as well as permanent protection of both forest reserves. It is hoped that with increased public awareness and proactive action from the government, Malaysian signature species, including majestic hornbills, elephants, tigers and tapirs, can remain alive in the wild rather than as stuffed museum specimens.

Click Me to help save Temengor, Belum rainforest

In April 2006, MNS (BirdLife in Malaysia) launched a campaign to save the Belum Temengor Forest Complex. The campaign aims to educate the public about the issues involved and to encourage the State and Federal governments to protect this critical area. Ideally, this would entail an end to all logging, as well as permanent protection of both forest reserves. It is hoped that with increased public awareness and proactive action from the government, Malaysian signature species, including majestic hornbills, elephants, tigers and tapirs, can remain alive in the wild rather than as stuffed museum specimens.

mohandasgandhi:

Ocean acidification: Connecting science, industry, policy and public

A powerful short film on Ocean acidification: Connecting science, industry, policy and public.

Ocean acidification is a recently recognised phenomenon which results from the growing quantities of carbon dioxide (CO2) in the Earth’s atmosphere. Much of this gas is being absorbed at the ocean surface, pushing seawater down the pH scale towards acidity and posing a potential threat to marine ecosystems and those dependent on them. As scientific research reveals more about how the oceans and the life they contain might be affected, there is a need to engage with a wider community including policy makers, environmental managers and the general public to understand what is happening, how we might be affected and what actions could be taken to reduce any risks.

(Read more)

If you are currently unaware of what ocean acidification is or the threats posed by acid deposition, I highly suggest watching this 12 minute film or getting through as much of it as you can.  Ocean acidification has been called “global warming’s evil twin” in that it’s more than likely as much of a threat or greater than global warming itself. 

I talk about the oceans a lot on this blog because their well-being is critical to sustaining life on land.  The two targets that stand to lose the most to ocean acidification are phytoplankton, which are the fundamental units in the web of life, producing 50% of the world’s oxygen and acting as the most basic components of the food chain, and coral reefs.  If we lose our oceans, we lose everything. The well-being of life on land and our ecosystems are both sustained with rich oceanic biodiversity. A sustainable environment starts with our oceans.

It takes potentially thousands of years to reverse the effects of ocean acidification but we can stop it. 

Please do your part and help get ocean acidification included in the National Climate Assessment.

mad-as-a-marine-biologist:

I’m not even joking.

The Authors have released ‘Conservation Biology For All’ as a free and open access format in an effort to make conservation knowledge available to as many people as possible.

Features

Provides an invaluable toolkit for a large and under-resourced audience of students in developing nations

Includes contributions from the top names in conservation biology who have contributed specific “hot topics” including tropical deforestation, invasive species, climate change, and ecosystem functioning

Addresses the key issues in conservation biology, clearly stating the challenges but also offering solutions