Gorilla DNA sequenced


This video is called Evidence of Common Ancestry: Human Chromosome 2.

From New Scientist:

Gorilla DNA unlocks secrets of our species

07 March 2012 by Sara Reardon

THANKS to Kamilah the gorilla, the last of the great apes has had its genome fully sequenced. The results highlight key similarities between us and gorillas – our second closest relatives after chimps.

Richard Durbin of the Sanger Institute in Cambridge, UK, led the international team that pieced together the western lowland gorilla (Gorilla gorilla gorilla) genome using several different sequencing techniques. The genome contains more than 3 billion pairs of DNA letters – roughly the same as humans – and includes about 21,000 genes.

Researchers can now compare the gorilla genome with chimpanzee and human genomes to study the origin of our species.

Early analysis suggests that the gorilla lineage splintered off from other great apes about 10 million years ago, some 3 million years before chimps and humans split. It’s no surprise, then, that chimps and humans have more in common: the sequences found in 70 per cent of great ape genetic material are more closely related in chimps and humans than in gorillas and either species.

But despite the ancient split, the remaining 30 per cent of Kamilah’s genome turned out to be more closely related to humans or chimps than those species are to one another, suggesting that genes continued to trickle between the three lineages after they split (Nature, DOI: 10.1038/nature10842).

Aylwyn Scally of the Sanger Institute says the most likely explanation is that gorilla ancestors interbred with the ancestors of humans and chimps, much like early modern humans and Neanderthals did.

The researchers also roughly sequenced an eastern lowland gorilla‘s genome (Gorilla beringei graueri) to compare it with Kamilah’s. The two subspecies separated 1.75 million years ago and now live 1000 kilometres apart in Africa. Here, too, the genomes hint at occasional interbreeding.

That seems to be quite common, says Scally. “Fifteen million years ago [long before the great apes split] was a good time to be an ape,” he says, as the climate and vegetation facilitated their spread and diversification. But as the climate changed, populations fragmented, evolved separately, and the small splinter groups either died out or found creative ways to carry on, such as breeding with other groups.

In this brave new primate world, gorillas rapidly evolved into a distinct species. Kamilah’s genome shows that after gorillas split off from other apes, some 500 genes changed more rapidly than the rest. Many of these genes are involved in hearing and brain development, and are the same as those that evolved quickly in human ancestors after they split from chimps. Some had speculated that their rapid evolution in humans could explain why we evolved language and chimps did not. Kamilah’s genome has thrown cold water on that idea: the gorilla and human versions of the genes are nearly identical.

See also here.

Why did the bipedal ape lose its fur and cross the globe? The 10 biggest puzzles of human evolution: here.

April 2012. New research reveals that like humans, wild chimpanzees – our closest living relatives – are unable to resist the temptation of succulent fruits such as mango and papaya grown by their human neighbours. These findings are perhaps unsurprising as chimps in zoos are notoriously partial to fruits like bananas, and are considered specialist fruit-feeders in the wild: here.

HUMANS aren’t the only primate to risk the reproductive repercussions of a diet rich in oestrogen-like compounds. Gorillas and colobus monkeys both eat large quantities of plants containing the chemicals, which can disrupt reproduction but have been shown to protect against some cancers: here.

Baby rollers’ vomiting self-defence


News about the Eurasian relatives of this and this roller species which I liked to see so much in the Gambia.

This is a French video on the Eurasian roller.

From AFP news agency:

‘Vomit Bird’ Throws Up a Defense Against Predators

Babies of a bird species called the Eurasian Roller vomit a foul-smelling orange liquid as a defense mechanism.

Wed Mar 7, 2012 12:04 PM ET

THE GIST

The baby Eurasian Roller’s defense involves vomiting a noxious substance onto itself.
When a bird is covered in vomit, it becomes less attractive as a snack, plus the parents smell the liquid and rush back to their nestlings.

Offspring of the bright-blue jackdaw-sized bird — Latin name Coracias garrulus — throw up the repugnant fluid when they are frightened in their nests, according to a paper appearing on Wednesday in the journal Biology Letters.

Covered in vomit, the nestlings not surprisingly become less attractive as a snack, the team says.

But the smell also alerts parents, returning to the nest, that a threatening incident has happened in their absence, they believe.

The scientists tested the “olfactory cue” theory by visiting nests with 10-day-old nestlings inside.

They used a small paintbrush to daub a tiny amount of either lemon juice or vomit on the inside of the nest. Parents returning to a vomit-treated nest reacted with great caution, delaying the time when they would settle in the home.

Previous research has found that birds have a surprisingly wide range of defensive reactions.

For instance, the northern fulmar (Fulmaris glacialis) yawks up stomach oils against intruders that makes them lose their waterproof coating.

And the common eider (Somateria mollissima) and northern shoveler (Anas acuta) have the ability to spray feces on their eggs to deter mammal egg-thieves.

However, the Eurasian roller is the first bird that has been found to use a scent, derived in response to a threat, as a means of communication, says the paper.

In that regard, it joins many other animals, from insects to humans, that use the “smell of fear” to warn fellow members of their species of an attack.

The study is led by Deseada Parejo of Spain’s Estacio Experimental de Zonas Aridas.

Common sandpiper photo from Gambia


8 February 2012 in the Gambia.

Near Njau village.

Common sandpiper, Njau, the Gambia, 8 February 2012

Just before the Egyptian plover landed on the river bank, there was already a common sandpiper there.

This is that common sandpiper.

Common sandpipers nest in Europe and Asia. In winter, they can be found in Africa, some even much further south than the Gambia, like in South Africa. Some winter in southern Asia and Australia.

Waders in Gambia: here.

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