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Study sheds light on why some grey squirrels are black
Black squirrels are the same species as grey squirrels, the only difference being their fur colour. 

Findings point to faulty pigment gene obtained from fox squirrels

Scientists at Anglia Ruskin University have shed new light on the origins of black squirrels.

Published in BMC Evolutionary Biology, the study found that the black fur is caused by the grey squirrel having a faulty pigment gene - a gene also found in the closely-related fox squirrel.

The fox squirrel, which is native to North America, also has black variants. Testing on grey and fox squirrels across the US and Canada revealed that other “signatures” on the mutated gene are more closely related to the fox squirrel.

Researchers say this suggests that the mutation first arose in the fox squirrel and was passed to the grey squirrel through interbreeding.

“Squirrels take part in ‘mating chases’ where a female squirrel is pursued by lots of male squirrels and eventually one male mates with the female,” explained study leader Dr Helen McRobie.

People have spotted ‘mixed species’ mating chases, with a mix of grey and fox squirrels pursuing a female. The most likely explanation for the black version of the gene being found in the grey squirrel is that a male black fox squirrel mated with a female grey squirrel.”

She continued: “The fact black grey squirrels have become so common right across North America is possibly because black fur offers a thermal advantage, helping them inhabit regions with extremely cold winters. This may have contributed to the expansion of the grey squirrel’s range during the past 11,000 years, following the end of the most recent ice age, helping them spread further north into Canada.”

Black squirrels in the UK are believed to have escaped a private zoo after being imported from the US. They are the same species as grey squirrels, the only difference being their fur colour.

The first wild black squirrel was recorded in Woburn, Bedfordshire, in 1912. Today, they can be found across much of south-east England.  

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Endangered turtles rescued from smugglers

News Story 1
 A group of endangered turtles have found a new home at London Zoo after being rescued from smugglers.

The four big-headed turtles arrived at the zoo at the end of last year, after smugglers tried to illegally import them to Canada, labelled as toys.

One of the turtles, named Lady Triệu after a Vietnamese warrioress, has moved to a new exhibit in the zoo’s reptile house. She is the only one of her kind in a UK zoo.

Big-headed turtles have such large heads that they cannot pull them back into their shells. To compensate, they have armour plating from head to tail and a very sharp beak to fend off predators. They are ranked number 18 on ZSL’s EDGE of Existence reptile list, which puts threatened species at the forefront of conservation action. Image © ZSL  

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RCVS Fellowship board chair elections get underway

Voting for the 2019 RCVS Fellowship Chair election is now underway. This year four candidates are standing for election, including Dr Robert Huey, Professor John Innes, Professor Liz Mossop and Professor Ian Ramsey.

The Chair will attend and preside over Fellowship meetings and take the lead in consolidating the Fellowship’s position as the learned society of the RCVS. Fellows will receive an email containing a link to the online voting form, as well as candidates’ details and manifestos. Voting closes at 5pm on Thursday, 5 September.