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Thinking for a cooler world

Gianna Gruen | Ideas

Local biodiversity changes, but is not lost, study shows

With climate change and deforestation we typically focus on how biodiversity gets hit or disappears as a result. But a new study finds that biodiversity is not necessarily lost, but changes instead.

Forest in Northern Mozambique (Photo credit: CC BY 2.0: Maria Dornelas)

Forest in Northern Mozambique (Photo credit: CC BY 2.0: Maria Dornelas)

Maria Dornelas and her team from St Andrews University in Scotland investigated six million species living on land and in marine environments over the past 150 years. They found no distinctive pattern of species loss associated with any local community or ecosystem throughout this time. Instead they observed that species composition changed over time. The findings imply that a species is not necessarily under threat of extinction, just because it can’t be found in its “traditional” habitat any more. It may have simply been forced to migrate to another place – and not to its detriment. And this turnover of species in any given locale or community must have occurred faster than previously thought.

The researchers insist their findings do not dispute the fact that many species and habitats around the world are under threat. But they suggest that strategies to protect species should be revised to reflect the phenomenon of species turnover, which has so far been underestimated.

Date

April 17, 2014

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Klaus Esterluß | Marvel with us

Bigfoot, hairy creature of the forests

Bigfoot

Bigfoot, credit: Jana Dörfelt

When we start talking about Bigfoot, we are also talking about Sasquatch. Both describe the same tall, hairy human-like species that many people believe lives hidden in the forests. And there are a lot more names out there for similar creatures. According to “Abominable Science”, written by an paleontologist/geologist and an outspoken skeptic, the origin of all great American mysteries of apes lies in ancient storytelling. It all began with Native Americans who told stories about mysterious hairy people in the woods or on mountains.

The Sasquatch was just the most popular one. He is the Canadian version of Bigfoot and became popular because of J. W. Burns, a collector of local legends for a Canadian newspaper. It all happened during the 1920s and a long lasting legend was born: The real Sasquatch did not look like how it is pictured today. Performing a google picture search produces a lot of very hairy results. But native Americans talked about being in contact with hairy giants. According to Abominable Science (p.34), those giants were described as “basically giant indians” who lived in villages, knew fire, clothes and weapons, but avoided civilization. They were called hairy giants because they had long (head) hair.

The name Sasquatch persisted for quite a while. Almost 40 years later it gave way to Bigfoot – because of a publicity stunt. The town of Harrison Hot Springs funded a hunt for Sasquatch with $600, to celebrate the centennial of British Columbia. The legend of Sasquatch spilled over into the US and the name Bigfoot became increasingly popular the more Bigfoot-prints were found. But why Bigfoot? Well, in 1958 The Humboldt Times columnist Andrew Genzoli used the term in one of his articles to describe the discovery of a very large footprint. And since then people have almost exclusively used the name Bigfoot, a lot of more footprints have been found and shaky movies have been shot. A legend was born.

 

Date

April 17, 2014

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Sonia Phalnikar | Biodiversity & ...

Unraveling a ‘big cat’ DNA mystery

barbary lion skull

A Barbary lion skull at the Natural History Museum

It has all the makings of a historical thriller – scientists in the UK have used the ancient skulls of Barbary lions preserved in the Tower of London to piece together the origin of modern-day big cats. And, they’ve hit upon a vital clue in India which could help resurrect the extinct and majestic Barbary lion of North Africa. First off, what exactly is a Barbary lion? Once found in huge numbers across North Africa, extending from Egypt to Morocco, it had the most spectacular physical features of all lion species. That included an extensive mane, larger body and a more pointed crown and narrow muzzle. Also called the “Atlas lion,” it was reported to have different colored eyes to other lions. Scientists are divided over when and if Barbary lions really went extinct.

The last record of a Barbary lion is an animal shot in Morocco in 1927, though there is circumstantial evidence that Barbary lions may have survived in the wild in the Atlas Mountains till 1942. European zoos have also tended to claim that they have a Barbary lion or two but experts remain skeptical.

asiatic lion

The Asiatic lion is a distant, long-lost cousin of the Barbary, research shows

Now, a team led by Ross Barnett of Durham University, UK, has discovered that the majestic animal has close genetic links to the Asiatic lions that live in India. (Less than 400 Asiatic lions survive at present on the Kathiawar Peninsula of India and the species is listed as endangered by the International Union for the Conservation of Nature.)

Barnett’s team came to that conclusion after scientists sequenced mitochondrial DNA from museum-held specimens and from Barbary lion skulls discovered preserved in the Tower of London’s moat and believed to date back to the 14th and 15th century. The study was published in the journal BMC Evolutionary Biology. Barnett said he was surprised by the incredibly close relationship between the extinct Barbary lion from North Africa and the Asiatic lion from India. This, he said, could now get conservationists talking about resurrecting the subspecies and reintroducing lions into North Africa. “This has implications for any future attempts to reintroduce lions into North Africa,” Barnett said. “They could probably be re-seeded with Indian lions.” The researchers compared their findings with genetic sequences drawn from other lions living in Asia and across Africa to work out different subspecies of lion evolved. Their work shows that the single species of modern lions’ most recent common ancestor lived around 124,000 years ago.

Date

April 4, 2014

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Gianna Gruen | Marvel with us

5 of the most successful conquerors

When an animal invades a new habitat this does neither need jet fighters nor bombs. There is neither a political conflict about it, because normally, nobody recognizes the invasion until it’s too late – meaning that endemic species, to speak animals that are home in that habitat, are suppressed. Here, we present you those animals, that had the most successful strategy:

Black Squirrel CC BY 3.0 by BirdPhotos.com/wikipedia.com: http://en.wikipedia.org/wiki/File:Eastern_Grey_Squirrel.jpg

Black Squirrel CC BY 3.0 by BirdPhotos.com/wikipedia.com: http://en.wikipedia.org/wiki/File:Eastern_Grey_Squirrel.jpg

This little guy looks really sweet, right? Perhaps that a quite clever disguise to take an innocent and sweet look. At least, that’s how the Grey squirrel made it’s way from America to Europe – where it competes for nuts with the endemic Red squirrels.

Zebra Mussel - CC BY-SA 3.0 by GerardM, wikipedia.com: http://en.wikipedia.org/wiki/File:Dreissena_polymorpha.jpg

Zebra Mussel – CC BY-SA 3.0 by GerardM, wikipedia.com: http://en.wikipedia.org/wiki/File:Dreissena_polymorpha.jpg

Not really movable on itself, the Zebra mussel sneaked into North America in ship’s ballast water. Quite a clever way to hide, right? But nowadays the time to hide is over: it’s clogging water filters, pipelines and attaches to almost anything in it’s surrounding.

Asien Tiger, public domain by  Centers for Disease Control and Prevention's Public Health Image Library

Asien Tiger, public domain by Centers for Disease Control and Prevention’s Public Health Image Library

What do you think: Did the Asian tiger mosquito fly all the way from Southeast Asia into other parts of Asia and even to Europe? It is believed to be the most-widely distributed animal (being abundant in 28 countries outside of it’s native range)

Spanish Slug, public domain by Zwentibold

Spanish Slug, public domain by Zwentibold

The Spanish slug is not longer munching it’s way through Spanish and Portuguese lettuce patches, but conquered also other patches throughout Europe – it is not only that they thread agriculture, but are also considered a danger for natural ecosystems.

Goat, CC BY-SA 3.0 by Armin Kübelbeck, wikipedia.com: http://en.wikipedia.org/wiki/File:Hausziege_04.jpg

Goat, CC BY-SA 3.0 by Armin Kübelbeck, wikipedia.com: http://en.wikipedia.org/wiki/File:Hausziege_04.jpg

Harmless in most parts of the world, unexpectedly it is goats posing a threat on the biodiveristy of Galapagos Islands for example. Here it is considered to be the most damaging invasive species.

 

 

Date

March 21, 2014

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Klaus Esterluß | Marvel with us

Dude, you stink! – a list of species with a bad taste in perfume.

While looking up species for this list, a thought almost inevitably pops up in my mind. What would our daily lives be like if we were to share the characteristics of the species in this post. It could be kind of funny, but the world would stink terribly, that’s for sure. This is a list of just four species – but feel free to add to it in the comments section below. Let’s start:

Garlic Toad - Creative Commons Attribution-Share Alike 2.5 Generic // wikipedia: http://bit.ly/OqgzDB

Garlic Toad – Creative Commons Attribution-Share Alike 2.5 Generic // wikipedia: http://bit.ly/OqgzDB

First of all is a toad. It’s a pretty small one, just between 6,5 and 8 centimetres in length, even the color is not very remarkable. The toad is grey or brown. If you live somewhere between Europe to Western Asia you may have come across them without noticing. But if you stress this little fella, better run. The toad’s name is Garlic Toad, so you get an idea of what’s in store for you, right? If the toad is alarmed, it makes a very loud call and exudes a noxious secretion which smells like – yes, garlic.

Stink Bug - Creative Commons Attribution-Share Alike 3.0 Unported / wikipedia: http://bit.ly/NdTTWe

Stink Bug – Creative Commons Attribution-Share Alike 3.0 Unported / wikipedia: http://bit.ly/NdTTWe

The stink bug does not try to hide what it is. The bug stinks, again, if in distress. And also again, the smell reminds of a cooking ingredient – coriander in the bug’s case. The strongly smelling substance is secreted from pores on its chest. As an aside – one will probably like the smell, it seems to be down to your (human’s) DNA whether or not you’d find the smell unpleasant. And we stay in the kitchen: In Laos the bugs are commonly eaten and are regarded as delicious due to their extremely strong odor. Yummy.

Wolverine - Creative Commons Attribution-Share Alike 3.0 Unported / wikipedia: http://bit.ly/1kRlMSO

Wolverine – Creative Commons Attribution-Share Alike 3.0 Unported / wikipedia: http://bit.ly/1kRlMSO

We leave the insect world for the third species on our smelly list. The wolverine is not exactly what you would think about as a comic book reader. There are no metal implants in the skeleton, but it’s a hairy creature as well. The wolverine we are talking about here can be found in larger numbers in nothern Canada or Alaska, even in the boreal forests and the tundra in Russia. It belongs to the family of the weasels, but looks more like a little bear. That’s where one of it’s nicknames originates from: skunk bear. Yes, the skunk is up next to complete our list. But anyway, the wolverine has potent anal scent glands he uses for marking his territory (and sexual signaling of course). We won’t delve into this subject any further.

Skunk -  Creative Commons Attribution 3.0 Unported/ wikipedia: http://bit.ly/1cZ6Lfj

Skunk – Creative Commons Attribution 3.0 Unported/ wikipedia: http://bit.ly/1cZ6Lfj

Finally, the skunk. Skunks are mammals often found in the Americas. They are notorious for their anal scent glands, which they can use as a defensive weapon. Bad news is, they have two glands, one on each side of the anus. These glands produce a mixture of sulfur-containing chemicals which have a highly offensive smell. The odor is strong enough to ward off even bears and it can be really difficult to remove from clothing.

Date

March 15, 2014

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