Brown bears that “ dance ” and rub against more trees are more successful at mating, research shows

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Brown bears who rub against more trees than their peers have more kids and more partners, according to a new study.

Researchers at the University of Alberta studied the genomes of 213 individual brown bears in the Alberta Rocky Mountains to track their location and family.

They then compared it to previous DNA data to create a “family tree” and found hundreds of “sites” such as trees, poles, and poles that the bears wrote against.

The results showed that bears who rub more often and in more places fare better in members of the opposite sex and in the number of children produced.

For men, each site they rub against increases the number of partners by 1.38 times, and each additional rub increases the number of children by 1.37 times.

The results of that work suggest that ‘rubbing’ a tree may have a fitness component, making those who do it ‘more attractive’.

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Brown bears who rub against more trees than their peers or `` dance '' against the tree have more children and more partners, according to a new study.

Brown bears who rub against more trees than their peers or “ dance ” against the tree have more children and more partners, according to a new study.

Researchers at the University of Alberta studied the genomes of 213 individual brown bears in the Alberta Rocky Mountains to track their location and family.

Researchers at the University of Alberta studied the genomes of 213 individual brown bears in the Alberta Rocky Mountains to track their location and family.

THE BROWN BEAR (URSUS ARCTOS)

The brown bear (Ursus arctos) is found in Eurasia and North America – from parts of Russia and China to Iran, the US and Canada.

The brown bear is one of the largest living carnivores on land, rivaled in size by the polar bear.

There are thought to be at least 110,000 brown bears worldwide and they are ‘the least concern’ in terms of conservation threats.

They are described as nocturnal but actually have peak activity in the morning and early evening.

They have been shown to engage in the use of tools, exhibit advanced reasoning skills, and are mostly solitary.

“ As far as we know, all bears do this dance, where they rub their backs against the trees, stomp their feet and leave behind the scent of who they are, what they are and what position they are in, ” said co- author Mark Boyce.

“What we were able to show is that both males and females have more offspring when they rub, more surviving offspring when they rub, and they have more partners when they rub.”

The research team led by Boyce and postdoctoral researcher Andrea Morehouse identified and collected bear hair samples from 899 bear rub spots.

These included trees, fence posts, and utility poles, in the Alberta Rocky Mountains south of Highway 3 for four years from 2011.

The researchers saw the same relationships for female brown bears as well.

Females with more partners were detected with more rubs and more often than females with fewer partners.

For each additional rub and occasion where a female was detected, the predicted number of offspring increased 1.42 and 1.55 fold, respectively.

“It seems that bears in good shape are more vigorous and rub more, and that may be associated with reproductive success,” Boyce said.

They compared it to previous DNA data to create a

They compared it to previous DNA data to create a “family tree” and found hundreds of “sites” such as trees, poles, and poles that the bears wrote against.

For men, each spot they rub increases the number of partners by 1.38 times, and each extra 'friction' increases the number of children by 1.37 times.

The results of that work suggest that 'rubbing' a tree may have a fitness component, making those who do it 'more attractive'.

For men, each spot they rub increases the number of partners by 1.38 times, and each extra ‘friction’ increases the number of children by 1.37 times.

This study also showed that this rubbing behavior helps females with cubs avoid the territories of large males, often choosing marginal habitat near farm buildings or closer to roads.

“This is done by scent and the reason they do is that big males are notorious for killing cubs,” Boyce said. “Large males don’t get anywhere near a building, but for females with cubs that’s an acceptable risk.”

He added that further studies may also shed light on sexual selection in bears. While brown bears fight tooth and nail to protect their territories, which often include the territories of up to four females, females are in charge.

The research team led by Boyce and postdoctoral researcher Andrea Morehouse identified and collected bear hair samples from 899 bear rub spots

The research team led by Boyce and postdoctoral researcher Andrea Morehouse identified and collected bear hair samples from 899 bear rub spots

These include trees, fence posts, and utility poles, in the Alberta Rocky Mountains south of Highway 3 for four years from 2011

The researchers saw the same relationships for female brown bears as well

These include trees, fence posts, and utility poles, in the Alberta Rocky Mountains south of Highway 3 for four years from 2011

In fact, previous research has shown that more than 17 percent of all brown bear nests are sired by multiple males.

“Female choice is a big deal,” Boyce said. “In this study, we proposed an alternative hypothesis that female brown bears use the information obtained from olfactory cues from rubbing males during the season to choose the paternity of their offspring.”

The study, ‘The smell of success: reproductive success related to rubbing behavior in brown bears’, was published in PLOS ONE.

CAN BROWN BEARS BE RETURNED IN BRITAIN?

In March, it was revealed that brown bears may be making a comeback in the English forests.

A £ 5 million ($ 6.6 billion) project aims to reintroduce the animals on a seven-acre site on the outskirts of Bristol – complete with a treetop walkway for visitors to look down on.

Called Bear Wood, the plan would see Eurasian brown bears – who can grow up to 8ft long – raise their cubs just as they did in medieval England.

But the creatures wouldn’t be roaming wild at all – they’ll be securely fenced off, and caretakers would supplement their foraged diet to keep them well-fed.

The project could start in the summer if approved.

Bristol Zoological Society has already received donations towards the cost of the project, but it needs to find an additional £ 2 million ($ 2.6 million).

All buildings will be built to blend in with their environment, Bristol Zoo said.

And if the plan wasn’t ambitious enough, five European gray wolves, already living in the nearby Wild Place Project Nature Park, will be moved to a new home in Bear Wood.

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