Penis size does matter for bank voles, says study

The secret to social dominance for bank voles appears to be the size of their genitals, according to scientists.

The link was made by researchers from Europe who were studying the small brown mammals' reproductive behaviour.

The study, in Behavioural Ecology and Sociobiology, found dominant males had wider penis bones, also called baculum.

Although not present in humans, these bones are found in many other species of mammal but their exact function has not been confirmed.

The study was conducted by Dr Jean-Francois Lemaitre from the University of Liverpool with colleagues in France and Switzerland.

Bank voles live for a maximum of 18 months and females give birth to four or five litters per year.

"This species is particularly interesting for study... because females mate with several males during a single reproductive bout," explained Dr Lemaitre.

Researchers suggest that this competition may have driven evolutionary adaptations in genital anatomy to improve males' chances of reproduction.

To test their theory, the team collected wild bank voles in Cheshire and studied their lab-reared offspring to understand which were dominant and which were subordinate.

Read on...

By Ella Davies Reporter, BBC Nature

Very small male zebrafish use sneaky sex strategy

Small male zebrafish adopt sneaky tactics to improve their chances of reproducing, scientists have found.

Male zebrafish fertilise eggs after they are laid, a process of external fertilisation known as spawning.

Scientists from the University of Sheffield discovered that the most diminutive males were able to get between a female that had just laid eggs and larger, rival males.

This gave them first access to the eggs in order to fertilise them.

The findings are published in the journal Ethology.

Zebrafish are widely studied by scientists, particularly in genetic research.

There is now increasing interest in their behaviour, the study of which can shed light on how our distant aquatic ancestors evolved.

Fish society

The University of Sheffield team that carried out this study was interested in one particular element of zebrafish "society" - their hierarchy.

"You can spot the dominant males," explained Penelope Watt, the biologist who led the study. "You see them patrolling the tank, chasing smaller fish away."

She and her team wanted to find out more about the importance of this dominance in reproduction, so they carried out paternity tests on zebrafish embryos to see if dominant males fathered more offspring.

The team placed a single female into a tank with two males - one dominant male and one subordinate. The female was contained in a plastic cylinder covered in fine mesh, so she could smell the males but could not make contact with them.

After 24 hours, the scientists released the female, allowing the fish to spawn, with males and females releasing masses of eggs and sperm together at the base of the tank.

When the female was ready to lay eggs, males jostled for position close to her, explained Dr Watt. The closer a male was to a female, the better the chance he had of fertilising the eggs she produces.

When the team DNA-tested the resulting offspring, they found, as expected, that dominant males had fathered more offspring than subordinate animals.

But the "subordinates" that had the best chance of fathering offspring were the smallest.

"It's probable that the smaller males are sneaky males and they're more manoeuvrable," the scientists said. "They can get in between the female and the larger male."

Such sneaky mating strategies are seen in other fish species, and this finding supports the idea that, in some species, male fish evolved "sexual tactics" to compensate for their diminutive size.

Dr Watt added: "It's nice to find out something about their behaviour that we didn't expect.

"They're a more complex species than we've given them credit for."
By Victoria Gill Science reporter, BBC Nature
http://www.bbc.co.uk/nature/15010109

Light shed on bisexual and promiscuous deep-sea squid

Scientists have gained a rare glimpse into the sex life of the mysterious deep-sea squid.

By studying footage taken by underwater vehicles, US researchers have found that this rarely seen creature will often engage in same-sex mating.

They believe this is because encounters with potential mates in the dark depths are rare, and the squid may be unable to tell the sexes apart.

The study is published in the Royal Society journal Biology Letters.

The researchers looked at video footage taken over 20 years by Remotely Operated Vehicles (ROVs), most of which was recorded in the Monterey Submarine Canyon, off the coast of California.

The species that was observed is called Octopoteuthis deletron, a tentacled beast that measures about 12cm-long (5in), with impressive hook-lined arms. It was recorded between depths of 400m and 800m (1,300-2,600ft).

Until now, little was known about this creature's sex life, apart from the fact that the male uses a long, penis-like organ to deposit spermatophores, complex structures containing millions of sperm, onto a female, which are then absorbed into her tissue.

But by studying footage of this deep-sea squid, they were able to find out much more.

Indiscriminate insemination
Lead author Hendrik Hoving, from the Monterey Bay Aquarium Research Institute (MBARI), explained: "We did not observe two animals mating, but we found evidence of mating - sperm packages on males and females.

"Going through hours of video, we found that both males and females carry sperm packages.
"As the locations of sperm packages were similar in both sexes, we concluded that males mate with males and females."

The finding surprised the team, said Dr Hoving.

The researchers found equal numbers of female and male squid that had had sperm packages deposited on them, indicating that same-sex mating was as frequent as encounters between squid of the opposite sex.

The number of sperm packages that had been deposited also suggested that these animals were promiscuous, the researchers said.

This unusual behaviour, they said, may be explained by the fact the squid is boosting its chances of successfully passing on its genes in the challenging environment it lives in.

In the Royal Society paper the team writes: "In the deep, dark habitat where O. deletron lives, potential mates are few and far between.

"We suggest that same-sex mating behaviour by O. deletron is part of a reproductive strategy that maximises success by inducing males to indiscriminately and swiftly inseminate every [squid] that they encounter."

Following the study, the researchers now hope to use genetic techniques to determine the paternity of the sperm packages, so as to find out whether more than one male is trying to deposit its sperm on the males and females.
By Rebecca Morelle Science reporter, BBC News

http://www.bbc.co.uk/news/science-environment-14986769

Sneaky Squid: Why Small Males Have Big Sperm

ScienceDaily (Aug. 10, 2011) — Male squid (Loligo bleekeri) employ different reproductive strategies depending on their body size. Research published in BioMed Central's open access journal BMC Evolutionary Biology shows that the divergent mating behavior of male squid has resulted in the evolution of different sperm sizes.


Large male squid compete for females by courting them with flashy skin color-change displays. Once a female has chosen her partner they mate in an above and below position so that the male can place his sperm inside the female's oviduct. He remains with the female until she spawns, ensuring that his sperm fertilize her eggs and that no other males have a chance to mate with her. At the moment a female lays her eggs, small 'sneaker' males rush in and mate with her, head to head. These small males place packages of sperm by the female's mouth in the hope that their sperm have a chance of fertilizing the eggs as they leave the female's body.


When researchers from London and Japan looked at the sperm produced by small sneaker males and large consort males they discovered that the sperm produced by the sneaker males was larger than that of the consorts. Dr Yoko Iwata from University of Tokyo said, "Sperm size is likely to be an adaptation to fertilization environment, either inside the female or externally, rather than competition between sperm, because the fertility and motility of sneaker and consort sperm were the same."

Overall, the larger males' strategy resulted in higher paternity rates -- but for smaller males, who cannot win a female by fair means, being sneaky gives them a chance of passing on their genes.


http://www.sciencedaily.com/releases/2011/08/110809212436.htm

Python sex romp sparks search for 7m monster snake near Cairns

AN orgy of snakes is in danger of bringing the house down upon a Cairns sporting club.


About six scrub pythons, all at least 3.5m long, have been getting busy in a boatshed roof of the Yorkeys Knob-based Hekili Outrigger Canoe Club.

The pythons, which may also include a 7m female nicknamed "Nigini", have been making such a romantic ruckus, sections of the roof have started breaking away.

Two of the pythons have been caught by a snake catcher. However, the narrow sections of the roof where the rest of them are living has made them unreachable.

Hekili Outrigger Canoe Club coach Sue Lockwood said one of the large snakes startled a club member after it was seen poking out of the ceiling when she went to retrieve a canoe.

Dave Walton from Cairns Snake Removals caught a 3.5m python and a 4.5m python at the clubhouse yesterday. They will be released into the wild.

It is the second time in two years snakes have caused a ruckus at the building, with Mr Walton nearly catching Nigini back in 2009 before she gave him the slithery slip.

Mr Walton believed there were still four more pythons living in the roof, including the elusive female.

by Daniel Bateman

from The Cairns Post (Cairns) 20.07.11)

http://www.cairns.com.au/article/2011/07/20/174635_local-news.html

Less attractive fish have 'better sperm'

In a study of tropical guppies, scientists have found that the less attractive males have "better sperm".


The research revealed that colourful flamboyant-looking males "invest" in their appearance at the expense of their sperm quality.

This suggests, the scientists say, that there is a trade-off between different characteristics that help the male to reproduce.

The findings are described in the Royal Society journal Proceedings B.

Professor Jonathan Evans from the Centre for Evolutionary Biology at the University of Western Australia carried out the study.

He described how his findings supported "sperm competition theory", whereby females mate with several males and the quality and swimming speed of the sperm determine which male fathers the offspring.

Guppies are a particularly useful species in which to study this, because the males engage in two types of reproductive behaviour - courtship displays and non-consensual or "sneak" mating.

"Males that predominantly performed sneak matings were less ornamented but had faster swimming sperm than those that predominantly used courtship," explained Professor Evans.

He continued in the journal article: "The reproductive advantage enjoyed by attractive males might potentially be offset by the poor performance of their ejaculates during sperm competition."

Lecturer in bat-sex row is nutrition expert

By Katherine Donnelly
Tuesday, 18 May 2010
A lecturer who filed a complaint of sexual harassment against a colleague who showed her an article about the sex life of fruit bats is a highly regarded expert on clinical nutrition.

Dr Rossana Salerno Kennedy lectures in medical education at University College Cork.

The much-published academic, who has a special interest in nutrition and the elderly, is married to Professor Peter Kennedy, vice president of research at UCC.

Dr Salerno Kennedy could not be contacted for comment yesterday, as Dr Dylan Evans demanded that sanctions imposed on him after the fruit-bats article incident be reversed.

The offending article, published in an academic journal, detailed how fruit bats prolong copulation via oral sex and Dr Evans said he showed it to a number of colleagues on the same day, one of whom complained.

Dr Evans, who lectures in behavioural science, has had a two-year period of intensive monitoring and counselling imposed on him, which he fears will have implications for his chances of gaining tenure at UCC.

Details of the controversy appeared on a number of websites in recent days and sparked international interest.

UCC appointed an external team to investigate complaints made by Dr Salerno Kennedy about Dr Evans' behaviour towards her in the period up to November 2, 2009, the day he showed he showed her the fruit bats article, and about the incident itself.

In her letter of complaint, she said that November 2 was "not the first time Dr Evans has raised sexual subjects with me" and on that day she felt his behaviour was "inappropriate and offensive".

The investigators rejected the complaints about the period before November 2, but upheld the complaint about the fruit- bats article incident, although they ruled it was not Dr Evans' intention to cause offence.

UCC has reacted with anger to the publication of confidential documents. The college said it viewed "with the utmost gravity the fact that confidential documentation concerning an internal allegation of sexual harassment was posted to social media platforms, in contravention of university policy".

The college insisted "the rights of staff who may wish to take similar action in future would also be affected, were confidentiality to be broken."

Dr Evans, who is being supported by the Irish Federation of University Teachers, told the Irish Independent yesterday that he had not released any documents in the case.

He launched an online petition seeking support for the reversal of the sanctions and said he had received letters from leading academics, including Professor Patrick Bateson, Provost of King's College Cambridge.

Irish Independent

http://www.belfasttelegraph.co.uk/news/local-national/lecturer-in-batsex-row-is-nutrition-expert-14811250.html#ixzz0oJd0x0TK

Sex and the Single Snail

Study shows benefits of sexual reproduction over asexual.

By Fariss Samarrai
28 January 2010

Why have sex?

That is one of the big questions in evolutionary biology.

Sexual reproduction is a high-energy endeavor, requiring, often, the quest for a mate, the actual act of sex, and the carrying of offspring (almost always by the females).

Why not reproduce asexually? Many organisms do, though most of them are single-celled bacteria and other simple life forms. Still, some multicellular organisms also reproduce asexually, including many plants, insects, some reptiles, various mollusks and a few fishes.

This highly efficient mode of reproduction is a low-energy endeavor, requiring no search for a mate, no sexual act, and sometimes, no carrying of offspring. It also allows rapid and abundant proliferation, since all members of that population are female and able to produce offspring.

So, yes, why have sex?

The prevailing theory is that sexual reproduction, which requires two genders, allows genetic intermingling that overall is very good for both the individuals and the species as a whole.

Asexual reproduction, on the other hand, is largely static, where each offspring is genetically identical to every other. This allows for the ongoing accumulation and replication of harmful mutations and little room for adaptation to rapidly changing environments, such as the introduction or quick proliferation of a pathogen. This could, in the long run, lead to extinction of the species.

A new study, by researchers at the University of Virginia and the University of Iowa, published currently in the journal Molecular Biology and Evolution, provides additional credence to this understanding.

“We demonstrated that sexual reproduction allows organisms to clean deleterious mutations from their genome,” said U.Va. biology professor Doug Taylor, who co-authored the study. “Asexual reproduction does indeed allow for the accumulation of deleterious mutations.”

Taylor and his colleagues at Iowa sequenced the entire mitochondrial DNA of multiple sexual and asexual lineages of a species of snail, Potamopyrgus antipodarum, which has sexual and asexual individuals living side-by-side in lakes in New Zealand.

They found that the sexually reproducing variety accumulates harmful mutations in DNA at about half the rate of the asexual lineage. This does not mean that mutations occur at a slower rate, but that, when mutations do occur, they are cleaned from the genome twice as fast in the sexual lineage.

“Asexual lineages suffer from the fact that they can’t clean the mutations from the genome—that’s the theory,” Taylor said. “And we found that, indeed, the sexual lineages are able to purge the genome of their deleterious mutations much more effectively than the asexual lineages.”

Taylor said the finding might be a profound demonstration, at the genetic level, for why sexual reproduction exists in the first place.

Taylor and his colleagues looked for mutations in the snails’ mitochondrial genome, in part because the mitochondrial genome is small and evolves rapidly in most animals. However, the mitochondrial genome is also where many mutations are known to affect the overall health of the full organism.

Underlying genetic disorders in the mitochondria are believed to cause many diseases affecting organisms, such as—in humans—Parkinson’s disease, premature aging, optic neuropathies and muscular degenerative disorders.

http://news.clas.virginia.edu/x16422.xml
(Submitted by T. Peter Park)

Safari Park Seeks New Homes For Hippos

11:50am UK, Wednesday December 23, 2009

Dominic Waghorn, Middle East correspondent

A safari park in Israel is looking for loving homes for hippos this festive season after a baby boom among its residents.

"Mud, mud, glorious mud. Nothing quite like it for cooling the blood," goes the song, but the opposite seems to be true at Ramat Gan safari park near Tel Aviv.

An abundance of mud and other factors seem to have warmed the ardour of its hippos to boiling point.

The park has undergone a breeding bonanza and is now coping with a surplus of the huge riverine beasts.

"They are very fertile animals." Safari zoologist Amelia Turkel told Sky News.

"The pregnancy is short for such large animals. It's only eight months. So a female can have one calf every year."

Ms Turkel and colleagues believe the warm Israeli sunshine and the park's watering hole ape conditions in Africa so well that the hippos are as relaxed and amorous as they would be in the wild.

What began as a group of five hippos is now a herd of more than 40.

The hippo baby boom at Ramat Gan has required urgent and extreme remedies.

As with humans, too many hippos in one place causes social problems.

"We were having social issues with them so it was a good thing to try and see if we could find homes for the young males and young females," the zoologist said of the fights that began breaking out between young adults.

"We could see the results of these fights because they would be scarred up the next morning.

"They have these enormous incisors and there are four of them in their mouths. (They are) very wide and very sharp and these teeth can inflict serious damage on other hippos."

The solution has been to ship the surplus hippos to loving homes in zoos worldwide making Ramat Gan the world's biggest exporter of the animals.

It is no easy task. The hippos must be sedated at night as far away as possible from the park's lake to avoid them running into the water and drowning.

The three-and-a-half-ton beasts are then lifted by bulldozer and put in crates. The smaller ones can be flown overseas. Bigger ones go by ship.

Fourteen hippos have been sent to countries as far and wide as Vietnam, Kazakhstan, Turkey and Ukraine.

There is apparently a long waiting list, but with Ramat Gan's enviably high breeding rate, there are plenty more where they came from.

See video and photo gallery at: http://news.sky.com/skynews/Home/World-News/Tel-Avivs-Ramat-Gan-Safari-Park-Looking-For-New-Homes-After-Hippo-Breeding-Excess/Article/200912415507016?f=rss

Rare deer breed at Kanpur zoo

Abhinav Malhotra, TNN
5 November 2009

KANPUR: Here is a piece of good news for all nature and wildlife lovers. Three Thamin deer (critically endangered specie of deer) have recently given birth to healthy fawns (one each) at the Kanpur zoological park.

Thamins, which are also known as 'Brow Antlered Deer' or 'Dancing Deer' or 'Sangai Deer' or ' Manipuri Deer', come under the schedule one of the highly endangered species of the Wildlife Protection Act, 1972 and have a maximum life span of only 10 years. The International Union for Conservation of Nature and Natural Resources has, therefore, placed Thamins in the highly endangered specie and thus this animal has been accorded the highest protection to save it from extinction. The Thamin deer are medium in size and very much look-alike of 'Barahsingha' in appearance.

Extremely excited with the birth of Thamin calf, director, Kanpur zoo, while talking to TOI said: "It is indeed a matter of happiness that Thamins, which come under the schedule-I of the Wildlife Act and once at the verge of extinction in India, is doing pretty well here at the Kanpur zoo. Three female Thamins have given birth to healthy fawns. The visitors too have a reason to smile as they will also get ample opportunity to see this rare specie deer, seen very rarely at other zoos of the country."

"Last year, female Thamins gave birth to four fawns. This year too, the fawn will gradually grow healthy like those of last year's. We are taking special care by doubling the protein diet at the same time providing calcium and multivitamin to the lactating female Thamin," informed a jubilant Rao.

Another senior zoo official, while speaking on the reasons why Thamins were on the verge of extinction, informed: "One of the main reasons for the diminishing population of the Manipur Brow Antlered deer is too much hunting. The destruction of their habitat has further worsened the situation."

The Dancing Deer which are herbivorous and survives on a variety of water plants, grasses, herbaceous plants and shoots, prefers to stay in open Indian parkland areas or light woodland near rivers or wet marshy land. One can hardly find them in thick forests or woodland. They are endemic to Loktak pond and are found in Keibul Lamjao National Park in Manipur.

They have always been a cause of worry for the wildlife lovers due to their depleting numbers. Once estimated to be around 100 in 1955, Thamins are just 363 (according to the Central Zoo Authority's inventory report published for the year 2008-09) in numbers at present. Out of which, presently there are around 180 Thamins in Keibul Lamjao National Park in Manipur. To save the population from any eventuality ex-situ conservation of this animal is being done in various zoological parks of India and Kanpur zoological park is one of them where, after providing conducive environment, the Thamins are doing absolutely well and the breeding is successfully going on.

http://timesofindia.indiatimes.com/city/kanpur/Rare-deer-breed-at-Kanpur-zoo/articleshow/5200984.cms

Rare deer breed at Kanpur zoo

Abhinav Malhotra, TNN
5 November 2009

KANPUR: Here is a piece of good news for all nature and wildlife lovers. Three Thamin deer (critically endangered specie of deer) have recently given birth to healthy fawns (one each) at the Kanpur zoological park.

Thamins, which are also known as 'Brow Antlered Deer' or 'Dancing Deer' or 'Sangai Deer' or ' Manipuri Deer', come under the schedule one of the highly endangered species of the Wildlife Protection Act, 1972 and have a maximum life span of only 10 years. The International Union for Conservation of Nature and Natural Resources has, therefore, placed Thamins in the highly endangered specie and thus this animal has been accorded the highest protection to save it from extinction. The Thamin deer are medium in size and very much look-alike of 'Barahsingha' in appearance.

Extremely excited with the birth of Thamin calf, director, Kanpur zoo, while talking to TOI said: "It is indeed a matter of happiness that Thamins, which come under the schedule-I of the Wildlife Act and once at the verge of extinction in India, is doing pretty well here at the Kanpur zoo. Three female Thamins have given birth to healthy fawns. The visitors too have a reason to smile as they will also get ample opportunity to see this rare specie deer, seen very rarely at other zoos of the country."

"Last year, female Thamins gave birth to four fawns. This year too, the fawn will gradually grow healthy like those of last year's. We are taking special care by doubling the protein diet at the same time providing calcium and multivitamin to the lactating female Thamin," informed a jubilant Rao.

Another senior zoo official, while speaking on the reasons why Thamins were on the verge of extinction, informed: "One of the main reasons for the diminishing population of the Manipur Brow Antlered deer is too much hunting. The destruction of their habitat has further worsened the situation."

The Dancing Deer which are herbivorous and survives on a variety of water plants, grasses, herbaceous plants and shoots, prefers to stay in open Indian parkland areas or light woodland near rivers or wet marshy land. One can hardly find them in thick forests or woodland. They are endemic to Loktak pond and are found in Keibul Lamjao National Park in Manipur.

They have always been a cause of worry for the wildlife lovers due to their depleting numbers. Once estimated to be around 100 in 1955, Thamins are just 363 (according to the Central Zoo Authority's inventory report published for the year 2008-09) in numbers at present. Out of which, presently there are around 180 Thamins in Keibul Lamjao National Park in Manipur. To save the population from any eventuality ex-situ conservation of this animal is being done in various zoological parks of India and Kanpur zoological park is one of them where, after providing conducive environment, the Thamins are doing absolutely well and the breeding is successfully going on.

http://timesofindia.indiatimes.com/city/kanpur/Rare-deer-breed-at-Kanpur-zoo/articleshow/5200984.cms

Why do animals, especially males, have so many different colors?

RIGHT: A male Hetaerina occisa damselfly with red spots at the base and tip of its wings.

October 31, 2009
By Stuart Wolpert

(PhysOrg.com) -- In new research, UCLA scientists claim that "secondary sexual traits" like coloring may let animals know which species to avoid fighting.

Why do so many animal species — including fish, birds and insects — display such rich diversity in coloration and other traits? In new research, Gregory Grether, UCLA professor of ecology and evolutionary biology, and Christopher Anderson, who recently earned his doctorate in Grether's laboratory, offer an answer.

At least since Charles Darwin, biologists have noticed that species differ in "secondary sexual traits," such as bright coloring or elaborate horns, Grether said. Darwin attributed this diversity to sexual selection, meaning the traits increased an animal's ability to attract mates.

But Grether and Anderson, writing in the Oct. 28 issue of the journal Proceedings of the Royal Society B: Biological Sciences, emphasize another evolutionary factor.

"The cost of attacking the wrong type of male and of being attacked by the wrong type of male favors the rich diversity of coloration and of birdsong and chemical cues, such as odors, to identify rivals," Grether said.

Grether and Anderson studied several species of the Hetaerina damselfly (closely related to dragonflies) and found that differences in coloration served to help damselflies distinguish males of their own species, who are rivals, from those of other species, who are not.

"We found that male Hetaerina damselflies use species differences in wing coloration to distinguish between intruders of their own species and intruders of other damselfly species, but only at sites where the two species naturally occur together," he said. "This provides one of the clearest demonstrations yet of an evolutionary process that is probably very prevalent in nature but which has largely been overlooked. We tested for shifts in what animals recognize as competitors."

Nobel Prize-winning Austrian ethologist and zoologist Konrad Lorenz suggested in 1962 that the spectacularly diverse coloration of coral reef fish was likely due to selection against fighting with the wrong species.

"Just as there could be selection against mating with the wrong species, there can also be selection against fighting with the wrong species," Grether said. "Lorenz said there was no advantage to coral reef fish attacking species that are close in proximity but are not competitors. The idea never really reached the level of attention in evolutionary biology that it deserved."

Lorenz's idea may not accurately explain the color diversity of coral reef fish, Grether said, but it may explain the diversity of coloration of other animal groups.

"When species are found in the same location, they do a better job of telling apart males of their own species from males of the other species than they do in places where they do not occur together," Grether said.

At sites where only one damselfly species occurs naturally, the researchers tested their theory by using members of that species whose wings had been artificially colored to resemble males of another damselfly species.

"We can test their responses at both kinds of sites, and we found they show greater discrimination between males of their own species and of other species at places where they actually have to contend with the other species than at places where they don't. They differentiate based on color," Grether said. "That this ability has evolved as a result of selection against fighting with other species is suggested quite strongly by the fact that in places where the other species do not occur, they do not make that distinction.

"If there is no reason for two species to interact aggressively with each other — as Lorenz argued with coral reef fish — then you would expect evolution to favor the ability for them to tell the difference by, for example, an exaggeration in the initial difference in color between them," Grether said. "Differences in color might enable females to more readily tell their own males apart from males of other species. Selection against interspecies aggression could favor the evolution of increased differences between species in color."

Some damselflies species also differ more in coloration where they occur together than where they occur alone, but "this finding can be explained either by selection against mating with the wrong species or selection against fighting with the wrong species," Grether said.

In future research, Grether hopes to learn what proportion of species can tell the difference between members of their own species and members of other species and whether they respond more strongly to their own species in a competitive context. Interspecies aggression and the evolutionary effect it has are understudied scientific questions, Grether said.

In addition to studying several species of damselflies in Mexico and Texas, Grether and Anderson collaborated with modeler Kenichi Okamoto to construct a mathematical model of what happens when species with similar secondary sexual traits come into contact. The model, published in the November 2009 issue of the journal Biological Reviews, predicts rapid evolutionary shifts in secondary sexual traits and also in what the animals recognize as competitors.

"My reading of the evidence," Grether said, "is that these evolutionary processes are important."

http://www.physorg.com/news176195425.html

Why do animals, especially males, have so many different colors?

RIGHT: A male Hetaerina occisa damselfly with red spots at the base and tip of its wings.

October 31, 2009
By Stuart Wolpert

(PhysOrg.com) -- In new research, UCLA scientists claim that "secondary sexual traits" like coloring may let animals know which species to avoid fighting.

Why do so many animal species — including fish, birds and insects — display such rich diversity in coloration and other traits? In new research, Gregory Grether, UCLA professor of ecology and evolutionary biology, and Christopher Anderson, who recently earned his doctorate in Grether's laboratory, offer an answer.

At least since Charles Darwin, biologists have noticed that species differ in "secondary sexual traits," such as bright coloring or elaborate horns, Grether said. Darwin attributed this diversity to sexual selection, meaning the traits increased an animal's ability to attract mates.

But Grether and Anderson, writing in the Oct. 28 issue of the journal Proceedings of the Royal Society B: Biological Sciences, emphasize another evolutionary factor.

"The cost of attacking the wrong type of male and of being attacked by the wrong type of male favors the rich diversity of coloration and of birdsong and chemical cues, such as odors, to identify rivals," Grether said.

Grether and Anderson studied several species of the Hetaerina damselfly (closely related to dragonflies) and found that differences in coloration served to help damselflies distinguish males of their own species, who are rivals, from those of other species, who are not.

"We found that male Hetaerina damselflies use species differences in wing coloration to distinguish between intruders of their own species and intruders of other damselfly species, but only at sites where the two species naturally occur together," he said. "This provides one of the clearest demonstrations yet of an evolutionary process that is probably very prevalent in nature but which has largely been overlooked. We tested for shifts in what animals recognize as competitors."

Nobel Prize-winning Austrian ethologist and zoologist Konrad Lorenz suggested in 1962 that the spectacularly diverse coloration of coral reef fish was likely due to selection against fighting with the wrong species.

"Just as there could be selection against mating with the wrong species, there can also be selection against fighting with the wrong species," Grether said. "Lorenz said there was no advantage to coral reef fish attacking species that are close in proximity but are not competitors. The idea never really reached the level of attention in evolutionary biology that it deserved."

Lorenz's idea may not accurately explain the color diversity of coral reef fish, Grether said, but it may explain the diversity of coloration of other animal groups.

"When species are found in the same location, they do a better job of telling apart males of their own species from males of the other species than they do in places where they do not occur together," Grether said.

At sites where only one damselfly species occurs naturally, the researchers tested their theory by using members of that species whose wings had been artificially colored to resemble males of another damselfly species.

"We can test their responses at both kinds of sites, and we found they show greater discrimination between males of their own species and of other species at places where they actually have to contend with the other species than at places where they don't. They differentiate based on color," Grether said. "That this ability has evolved as a result of selection against fighting with other species is suggested quite strongly by the fact that in places where the other species do not occur, they do not make that distinction.

"If there is no reason for two species to interact aggressively with each other — as Lorenz argued with coral reef fish — then you would expect evolution to favor the ability for them to tell the difference by, for example, an exaggeration in the initial difference in color between them," Grether said. "Differences in color might enable females to more readily tell their own males apart from males of other species. Selection against interspecies aggression could favor the evolution of increased differences between species in color."

Some damselflies species also differ more in coloration where they occur together than where they occur alone, but "this finding can be explained either by selection against mating with the wrong species or selection against fighting with the wrong species," Grether said.

In future research, Grether hopes to learn what proportion of species can tell the difference between members of their own species and members of other species and whether they respond more strongly to their own species in a competitive context. Interspecies aggression and the evolutionary effect it has are understudied scientific questions, Grether said.

In addition to studying several species of damselflies in Mexico and Texas, Grether and Anderson collaborated with modeler Kenichi Okamoto to construct a mathematical model of what happens when species with similar secondary sexual traits come into contact. The model, published in the November 2009 issue of the journal Biological Reviews, predicts rapid evolutionary shifts in secondary sexual traits and also in what the animals recognize as competitors.

"My reading of the evidence," Grether said, "is that these evolutionary processes are important."

http://www.physorg.com/news176195425.html

Chinese Fruit Bats Demonstrate Unusual Sexual Behavior Never Before Seen in Adult Animals

RIGHT: Greater short-nosed fruit bat feeding on kapok, photo: Wikipedia.

by Matthew McDermott,
New York, NY on 10.28.09
Science & Technology (science)

New research published in the online journal PLoS ONE demonstrates for the first time that a non-human adult animal species regularly engages in oral sex behavior. While the behavior has been seen in juvenile animals before, this is the first time it has been observed in adult animals. Warning: While the following information is scientifically accurate, some of the descriptions are slightly graphic.

Prepare to enter the fascinating world of fruit bat fellatio. Though it has been observed previously in bonobos (both heterosexually and homosexually), this behavior generally has been confined to juvenile animals, the authors of the new study note.

Activity May Increase Copulation Time

The field research, which was conducted in Guangzhou City, China, reveals that in the case of the greater short-nosed fruit bat (Cynopterus sphinx) female species-on-male species oral sex now has been documented as a regular occurrence. Scientists observed that in instances where oral sex was performed, copulation time increased.

Benefits of Longer Copulation

As to why this behavior occurs, the paper's authors propose several adaptive hypotheses that merit further study:

1. The activity may increase lubrication and thus prolong copulation, in turn assisting transport the transport of sperm or stimulating secretions in the female bat's pituitary gland, thereby increasing the likelihood of fertilization.



2. Prolonged copulation may be a form of "mate-guarding" -- that is, claiming a single a partner and protecting that partner against sexual activity with other bats.



3. The activity may help prevent sexually transmitted diseases, as saliva has "a protective repertoire that goes beyond antibacterial activity to include antifungal, antichlamydial, and antiviral properties as well," according to the report.



4. The activity may "facilitate the detection and identification of MHC-dependent chemical cues associated with mate choice," say the scientists.

Read the whole paper: Fellatio by Fruit Bats Prolongs Copulation Time (Warning: Contains some graphic descriptions.)

http://www.treehugger.com/files/2009/10/chinese-fruit-bats-engage-in-unusual-sexual-behavior.php

(Submitted by Joe McNally)

Chinese Fruit Bats Demonstrate Unusual Sexual Behavior Never Before Seen in Adult Animals

RIGHT: Greater short-nosed fruit bat feeding on kapok, photo: Wikipedia.

by Matthew McDermott,
New York, NY on 10.28.09
Science & Technology (science)

New research published in the online journal PLoS ONE demonstrates for the first time that a non-human adult animal species regularly engages in oral sex behavior. While the behavior has been seen in juvenile animals before, this is the first time it has been observed in adult animals. Warning: While the following information is scientifically accurate, some of the descriptions are slightly graphic.

Prepare to enter the fascinating world of fruit bat fellatio. Though it has been observed previously in bonobos (both heterosexually and homosexually), this behavior generally has been confined to juvenile animals, the authors of the new study note.

Activity May Increase Copulation Time

The field research, which was conducted in Guangzhou City, China, reveals that in the case of the greater short-nosed fruit bat (Cynopterus sphinx) female species-on-male species oral sex now has been documented as a regular occurrence. Scientists observed that in instances where oral sex was performed, copulation time increased.

Benefits of Longer Copulation

As to why this behavior occurs, the paper's authors propose several adaptive hypotheses that merit further study:

1. The activity may increase lubrication and thus prolong copulation, in turn assisting transport the transport of sperm or stimulating secretions in the female bat's pituitary gland, thereby increasing the likelihood of fertilization.



2. Prolonged copulation may be a form of "mate-guarding" -- that is, claiming a single a partner and protecting that partner against sexual activity with other bats.



3. The activity may help prevent sexually transmitted diseases, as saliva has "a protective repertoire that goes beyond antibacterial activity to include antifungal, antichlamydial, and antiviral properties as well," according to the report.



4. The activity may "facilitate the detection and identification of MHC-dependent chemical cues associated with mate choice," say the scientists.

Read the whole paper: Fellatio by Fruit Bats Prolongs Copulation Time (Warning: Contains some graphic descriptions.)

http://www.treehugger.com/files/2009/10/chinese-fruit-bats-engage-in-unusual-sexual-behavior.php

(Submitted by Joe McNally)

Neanderthals ‘had sex’ with modern man

October 25, 2009
Jonathan Leake, Science Editor

Modern humans and Neanderthals had sex across the species barrier, according to a leading geneticist who is overseeing a project to compare their genomes.

Professor Svante Paabo, director of genetics at the renowned Max Planck Institute for Evolutionary Anthropology in Leipzig, will shortly publish his analysis of the entire Neanderthal genome, using DNA retrieved from fossils. He aims to compare it with the genomes of modern humans and chimpanzees to work out the ancestry of all three species.

Modern humans arrived in Europe from Africa about 40,000 years ago to find Neanderthals already living there. The two species then co-existed for 10,000-12,000 years before Neanderthals died out — a fact that has caused endless academic speculation about whether they interbred.

Paabo recently told a conference at the Cold Spring Harbor Laboratory near New York that he was now sure the two species had had sex — but a question remained about how “productive” it had been.

“What I’m really interested in is, did we have children back then and did those children contribute to our variation today?” he said. “I’m sure that they had sex, but did it give offspring that contributed to us? We will be able to answer quite rigorously with the new [Neanderthal genome] sequence.”

Such an answer might ease the controversy over recent contradictory discoveries regarding Neanderthals. Some fossils seem to have both modern human and Neanderthal features, suggesting that the two species interbred. Yet DNA scans have shown that Neanderthal genes were very different from those of modern man.

Last week Professor Chris Stringer, head of human origins at the Natural History Museum, presented a conference at the Royal Society in London with an idea that could accommodate both sets of evidence.

“It’s possible that Neanderthals and humans were genetically incompatible, so they could have interbred but their children would have been less fertile,” said Stringer.

This phenomenon is seen in many other species such as when lions breed with tigers and horses breed with zebras.

“I used to believe Neanderthals were primitive,” said Stringer, “but in the last 10,000-15,000 years before they died out, around 30,000 years ago, Neanderthals were giving their dead complex burials and making tools and jewellery, such as pierced beads, like modern humans.”

Due to the length of time that has elapsed since Neanderthals became extinct, any trace of their DNA in modern humans could have been diluted below detectable levels. Paabo hopes to overcome this by scanning the Neanderthal genome for the genes of modern humans.

Click here to watch an interview with Professor Svante Paabo, who is overseeing the neanderthal genome project, where he talks about whether neanderthals and modern humans had sex.

http://www.timesonline.co.uk/tol/news/science/biology_evolution/article6888874.ece

(Submitted by Rob Chambers)

Neanderthals ‘had sex’ with modern man

October 25, 2009
Jonathan Leake, Science Editor

Modern humans and Neanderthals had sex across the species barrier, according to a leading geneticist who is overseeing a project to compare their genomes.

Professor Svante Paabo, director of genetics at the renowned Max Planck Institute for Evolutionary Anthropology in Leipzig, will shortly publish his analysis of the entire Neanderthal genome, using DNA retrieved from fossils. He aims to compare it with the genomes of modern humans and chimpanzees to work out the ancestry of all three species.

Modern humans arrived in Europe from Africa about 40,000 years ago to find Neanderthals already living there. The two species then co-existed for 10,000-12,000 years before Neanderthals died out — a fact that has caused endless academic speculation about whether they interbred.

Paabo recently told a conference at the Cold Spring Harbor Laboratory near New York that he was now sure the two species had had sex — but a question remained about how “productive” it had been.

“What I’m really interested in is, did we have children back then and did those children contribute to our variation today?” he said. “I’m sure that they had sex, but did it give offspring that contributed to us? We will be able to answer quite rigorously with the new [Neanderthal genome] sequence.”

Such an answer might ease the controversy over recent contradictory discoveries regarding Neanderthals. Some fossils seem to have both modern human and Neanderthal features, suggesting that the two species interbred. Yet DNA scans have shown that Neanderthal genes were very different from those of modern man.

Last week Professor Chris Stringer, head of human origins at the Natural History Museum, presented a conference at the Royal Society in London with an idea that could accommodate both sets of evidence.

“It’s possible that Neanderthals and humans were genetically incompatible, so they could have interbred but their children would have been less fertile,” said Stringer.

This phenomenon is seen in many other species such as when lions breed with tigers and horses breed with zebras.

“I used to believe Neanderthals were primitive,” said Stringer, “but in the last 10,000-15,000 years before they died out, around 30,000 years ago, Neanderthals were giving their dead complex burials and making tools and jewellery, such as pierced beads, like modern humans.”

Due to the length of time that has elapsed since Neanderthals became extinct, any trace of their DNA in modern humans could have been diluted below detectable levels. Paabo hopes to overcome this by scanning the Neanderthal genome for the genes of modern humans.

Click here to watch an interview with Professor Svante Paabo, who is overseeing the neanderthal genome project, where he talks about whether neanderthals and modern humans had sex.

http://www.timesonline.co.uk/tol/news/science/biology_evolution/article6888874.ece

(Submitted by Rob Chambers)

Brief encounters of the animal kind: Isabella Rossellini's Green Porno

Isabella Rossellini has found her calling, as the director and presenter of Green Porno, a series of beautifully hand-crafted short films about the sex lives of animals

There are certain things you don't expect to hear Isabella Rossellini say. Things like, "I have sex several times a day. Any opportunity. Any female." Or, "To have babies, I need to mate with another hermaphrodite in the 69 position." Or, "When needed, I can have an erection six feet long." But there are plenty of delightfully unexpected things about Green Porno, Rossellini's series of short films about the sex lives of animals, the second batch of which has just gone live on the Sundance Channel's website.

The first season, made last year, marked Rossellini's debut as a director. She had collaborated with Guy Maddin on My Dad Is 100 Years Old, a tribute to her film-maker father and fellow nature enthusiast Roberto, but she had always struggled over projects of her own that would stretch to television, let alone feature-length. When she learned that Sundance was fishing for attention-grabbing short content suitable for digital platforms, it proved the perfect outlet for her brief directorial attention span, as well as an opportunity to explore her longstanding love of zoology. "And when I thought 'capture people's attention,'" she says on a behind-the-scenes clip available at the project's microsite, one word came to mind. "Sex."

And so Green Porno was hatched. In each of these very short shorts – none lasts longer than three minutes and up to two-thirds of the running time is taken up with credits – Rossellini expounds with relish upon the mating habits of a particular species. Assuming the first person (or first creepy-crawly), she plays the male, garbed in a series of gloriously expressive handmade costumes in the bold colours and shapes suited to smaller screens; if the distribution model is hi-tech, the aesthetic approach, courtesy of Brooklyn-based artist-turned-production designer Andy Myers, is decidedly handcrafted. Byers' costumes are made mostly from paper, eschewing digital effects for hands-on craft. Think Michel Gondry meets David Attenborough in the Blue Peter studio after dark.

Rossellini takes the biology seriously. "When I write the script," she notes, "first I do the research, the scientific research, then I try to simplify it as much as I can and make it funny. Then I have to imagine how it can translate in this sort of theatre that we do here with puppetry and me dressed up as the animal ... It's funny but it's a little sick too. And also very informative."

In the first series, Rossellini enthusiastically portrayed, among other things, a bee bleeding to death after leaving its penis inside its mate (as they do), a mantis having its head rather frighteningly chewed off in flagrante delicto ("I keep copulating. Nothing stops me. I keep going! Sex!") and a snail clamped to its partner, dart-like appendages jabbing away ("I use them to inflict pain on my partners before mating – it turns me on. I love to be hurt too. Sadomasochism excites me"). The run ended with a strangely endearing shot of her severed head playing host to gestating maggots.

In the new batch, the theme has shifted underwater and the scale is no longer restricted to the miniature. Lessons are offered on the hydrodynamic shortcomings of a hefty whale penis, self-cloning among starfish and the extraordinary length, relative to its body, of the barnacle's nob. You haven't really lived until you've seen the look on Rossellini's face as a 20-foot handmade penis snakes its way from her clavicle to the other side of the room.

In fact, her charmingly sexy performance is integral to these shorts' successful character, whether she's strolling through a forest of eight-foot-tall, frilled, barbed and spiralling phalli or noting how important it is that her vagina's shape is "species-specific, so that I'm not screwed by a bear". What other actor could bring both coquettish charm and unbridled glee to the declaration "We are sequential hermaphrodites!" – delivered while wearing a limpet shell at a rakish angle?

http://www.guardian.co.uk/film/filmblog/2009/apr/01/isabella-rossellini-green-porno-sundance