Photo-monitoring Whale Sharks: Largest Fish In The Sea Appear To Thrive Under Regulated Ecotourism

Source:

http://www.sciencedaily.com/releases/2007/12/071226003604.htm

ScienceDaily (Dec. 29, 2007) — Up to 20 meters long and weighing as much as 20 tons, its enormous size gives the whale shark (Rhincodon typus) its name. Known as the 'gentle giant' for its non-predatory behavior, this fish, with its broad, flattened head and minute teeth, eats tiny zooplankton, sieving them through a fine mesh of gill-rakers. Listed as a rare species, relatively little is known about whale sharks, which live in tropical and warm seas, including the western Atlantic and southern Pacific.

However, a new study combines computer-assisted photographic identification with ecotourism to study the rare species and suggests whale shark populations in Ningaloo, Western Australia are healthy. The study appears in the Ecological Society of America's January issue of Ecological Applications.
West Australian marine scientist Brad Norman (ECOCEAN/Murdoch University) began the study in 1995. Photographs were taken while swimming alongside each whale shark and photographing or video-taping the white lines and spots along the flanks of the animal. Norman teamed up with U.S. computer programmer Jason Holmberg (ECOCEAN, Portland, Oregon) and astronomer Zaven Arzoumanian (USRA/NASA, Greenbelt, Maryland) who adapted software originally used with the Hubble space telescope. The pattern-recognition software developed by Holmberg and Arzoumanian allowed the group to positively identify individual whale sharks. Like a human fingerprint, the speckles and stripes pattern on the skins of whale sharks are believed to be unique to each individual.
Ningaloo Reef, in Western Australia, is one of the best locations to find whale sharks, especially between April and June. The authors found that more whale sharks are returning to the northern area of Ningaloo Marine Park from season to season, suggesting the population is growing. In addition, they found that about two-thirds of the sharks were repeat visitors while one-third were sighted only once during the study period.
The authors say their study suggests that the management guidelines for whale shark ecotourism at Ningaloo appear to be on target.
"Applying these guidelines to other locations along whale shark migration routes may offer a viable alternative to hunting these fish, one that yields both economic and conservation benefits," says Norman.
As a rare and highly migratory fish, whale sharks are a big draw for Ningaloo's ecotourism industry, where tourists pay to get close views and even swim with the sharks. In spite of their gargantuan size, whale sharks are fairly docile; the main risk comes from getting in the way of their very large and powerful tails.
Based on 5100 underwater images contributed by hundreds of researchers, divers, and ecotourists, the authors obtained almost ten times more data than any previous study.
"To study whale sharks in a meaningful way, we really had to rethink how we collect data and how we analyze it," says Holmberg. "The results surpassed our expectations, allowing hundreds of individuals to contribute and providing the necessary data to obtain a closer look at the population's health."
Norman and colleagues note that while their study is encouraging for the Ningaloo whale shark populations, global concern over their future is justified, especially in areas where the sharks continue to be hunted for their fins and meat. The researchers hope others will apply their techniques to other whale shark populations, as well as to other species.
Adapted from materials provided by Ecological Society of America.

Fausto Intilla

www.oloscience.com

Squirrels Use Old Snake Skins To Mask Their Scent From Predators

Source:

http://www.sciencedaily.com/releases/2007/12/071219130305.htm

ScienceDaily (Dec. 25, 2007) — California ground squirrels and rock squirrels chew up rattlesnake skin and smear it on their fur to mask their scent from predators, according to a new study by researchers at UC Davis.

Barbara Clucas, a graduate student in animal behavior at UC Davis, observed ground squirrels (Spermophilus beecheyi) and rock squirrels (Spermophilus variegates) applying snake scent to themselves by picking up pieces of shed snakeskin, chewing it and then licking their fur.
Adult female squirrels and juveniles apply snake scent more often than adult males, which are less vulnerable to predation by snakes, Clucas said. The scent probably helps to mask the squirrel's own scent, especially when the animals are asleep in their burrows at night, or to persuade a snake that another snake is in the burrow.
The squirrels are not limited to the use of shed snake skins, said Donald Owings, a professor of psychology at UC Davis who is Clucas' adviser and an author on the paper. They also pick up snake odor from soil and other surfaces on which snakes have been resting, and use that to apply scent. Other rodents have been observed using similar behavior.
Snake-scent application is one of a remarkable package of defenses that squirrels use against rattlesnakes, Owings said. In earlier work, Owings' lab has found that squirrels can: heat up their tails to send a warning signal to rattlesnakes, which can "see" in the infrared; assess how dangerous a particular snake is, based on the sound of its rattle; and display assertive behavior against snakes to deter attacks. In addition, work by Owings' colleague, psychology professor Richard Coss, has demonstrated that these squirrels have evolved resistance to snake venom.
"It's a nice example of the opportunism of animals," Owings said. "They're turning the tables on the snake."
The other authors on the paper, which was published Nov. 28 in the journal Animal Behavior, are Matthew Rowe, Sam Houston State University, Texas, and Patricia Arrowood at New Mexico State University. The work was funded by the National Science Foundation and the Animal Behavior Society.
Adapted from materials provided by University of California - Davis.

Fausto Intilla

www.oloscience.com

Why Diving Marine Mammals Resist Brain Damage From Low Oxygen

Source:

http://www.sciencedaily.com/releases/2007/12/071218192033.htm

ScienceDaily (Dec. 20, 2007) — No human can survive longer than a few minutes underwater, and even a well-trained Olympic swimmer needs frequent gulps of air. Our brains need a constant supply of oxygen, particularly during exercise.

Contrast that with Weddell seals, animals that dive and hunt under the Antarctic sea ice. They hold their breath for as long as 90 minutes, and remain active and mentally alert the whole time. The seals aren't fazed at all by low levels of oxygen that would cause humans to black out. What's their secret?
Certain animals--including dolphins, whales and sea otters--appear to be protected by elevated levels of oxygen-carrying proteins in their brains, according to a study by researchers at the University of California, Santa Cruz, led by Terrie Williams, professor of ecology and evolutionary biology. The team measured and compared the amounts of these complex oxygen-carrying proteins--called globins--in the cerebral cortex of 16 different mammalian species. The results suggest that some species have evolved the capacity to protect their brains from conditions of low oxygen, also called hypoxia.
"What was remarkable was the level of variability we found," said Williams. "Some animals had three to 10 times more neuroprotecting type globins than others. These wild species may hold many clues about how to turn on protective mechanisms in the mammalian brain."
The discovery could have important implications for understanding stroke and aging in humans, according to Williams. It's not yet clear whether animals of a particular species are born with high amounts of brain globins, or whether their behavior and environment stimulate the production of globins. But in either case, the amounts appear to be malleable. That's promising, she said, because if globin production could be boosted in humans, then brain damage due to disease or aging could potentially be minimized.
"The mammalian brain appears to have a remarkable capacity for increasing neuroprotective globins--we're seeing that in a comparative way in animals," Williams explained. "Could we take advantage of that" Could we retrain the human brain to improve our own survival" We don't know yet, but it's certainly intriguing and worth investigating."
Scientists have long wondered why marine mammals are so tolerant of hypoxia. The conventional wisdom was that they had evolved physiological adaptations that increased the delivery of oxygen to the brain--for example, higher capillary density and blood flow that could be shunted preferentially to the brain. But despite such adaptations, blood oxygen levels still plummet after just a few minutes underwater, according to recent studies by Williams's group and others. How marine mammals could keep their vital organs alive on such low levels of oxygen remained a mystery.
Some unknown factor seemed to be involved, and Williams's attention recently turned to new types of globins that were discovered in 2000. Called neuroglobins and cytoglobins, these oxygen-carrying proteins reside in the brain tissue. That distinguishes them from hemoglobin, a similar iron-containing protein complex that carries oxygen in the blood and circulates throughout the body. Another molecular relative, myoglobin, facilitates oxygen delivery only in muscle tissue.
Scientists are still investigating the physical chemistry of these brain globins. So far, the evidence suggests that cytoglobins could play a role in efficiently moving oxygen out of the blood and into the brain, even when oxygen levels are extremely low, Williams said. The brain's neuroglobins, on the other hand, appear to be able to grab reactive oxygen and prevent the formation of destructive free radicals. Together, she said, these two resident neuroglobins could help keep the brain functioning and well-protected against damage during hypoxia.
To test this hypothesis, Williams brought together a team that included molecular biologists, biochemists, and wildlife veterinarians. The researchers wanted to find out if the amounts and kinds of globins in the brain correlated with the physical activity patterns of various wild mammals. They collected brain tissue from 41 terrestrial mammals and 23 marine mammals representing 15 wild species and one laboratory species. These came from state animal control programs or were "found" animals that had died from roadkill, fisheries bycatch, or stranding.
For each brain sample, the team measured hemoglobin and resident neuroglobins--the neuroglobins and cytoglobins--in the cerebral cortex. In the laboratory of coauthor David Kliger, a professor of chemistry and biochemistry at UCSC, the researchers used a technique called spectrophotometry to identify and quantify the minute quantities of brain globins that were present at the time of the animal's death.
They found a striking difference in globin levels depending on whether the species was a terrestrial, swimming, or diving specialist, according to Williams. Compared to terrestrial mammals, marine species had higher amounts of hemoglobin--and their brain tissues were darker in color due to an abundance of iron.
But the study results weren't entirely as expected: the shallow-swimming and highly active dolphins, sea lions, and sea otters had higher amounts of resident neuroglobins than did the deep-diving whales. And then there was the bobcat. Unlike the dog-related species--foxes and coyotes--three bobcat individuals had surprisingly high amounts of resident brain globins.
"Maybe it's not just breath-holding that stimulates these globins, but high levels of activity, such as sprinting," Williams said.
The research hasn't completely solved the mystery, but it's a first step, said Mary Zavanelli, a lecturer in molecular, cell, and developmental biology at UCSC. Zavanelli developed the laboratory techniques for measuring the amounts and kinds of globins in brain tissue by analyzing gene expression. In this way, she confirmed the species differences.
"There won't be a quick answer because this is complicated biology," said Zavanelli. "But the techniques are straightforward and simple, so it's just a matter of focusing on our questions. The big problem is getting enough brain tissue that's in good shape, especially from found wild animals."
As this research project continues, it might expand to include an investigation of whether high levels of brain globins are correlated with long lifespans in certain species. Bowhead whales have been known to live as long as 211 years, Williams noted. That makes her wonder how their brains are protected and whether whales ever suffer from strokes.
"These animals may have solved the aging brain problem," she noted. "Neuroglobins might give us some clues as to how."
The study appears online December 18th in the Proceedings of The Royal Society B. Williams is lead author of the paper, entitled "Running, swimming and diving modifies neuroprotecting globins in the mammalian brain."
Other UCSC researchers involved in the study included graduate student Lucas Cantin and staff researcher Robert Goldbeck in Kliger's lab; campus veterinarian David Casper; and undergraduate Michael Morledge in Zavanelli's lab. The study's coauthors also include Melissa Miller of the California Department of Fish and Game's Marine Wildlife Veterinary Care and Research Center, and Ann Pabst and William McLellan of the University of North Carolina, Wilmington.
Adapted from materials provided by University of California - Santa Cruz.

Fausto Intilla

www.oloscience.com

Two New Mammal Species Discovered In Indonesia's Wilderness

Source:

http://www.sciencedaily.com/releases/2007/12/071217092939.htm

ScienceDaily (Dec. 18, 2007) — A tiny possum and a giant rat were recorded by scientists as probable new species on a recent expedition to Indonesia's remote and virtually unknown "Lost World" in the pristine wilderness of western New Guinea's Foja Mountains. The Foja Wilderness is part of the great Mamberamo Basin, the largest unroaded tropical forest in the Asia Pacific region.

During the June expedition, the team* documented two mammals, a Cercartetus pygmy possum, one of the world's smallest marsupials, and a Mallomys giant rat, both currently under study and apparently new to science. They also recorded the mating displays of several rare and little-known birds for the first time.
"The giant rat is about five times the size of a typical city rat," said Kristofer Helgen, a scientist with the Smithsonian Institution in Washington, D.C. "With no fear of humans, it apparently came into the camp several times during the trip."
The film crew obtained the first film documentation of several spectacular birds found in Foja, capturing on tape the full courtship displays of the golden-fronted bowerbird (Amblyornis flavifrons) and of the black sicklebill bird of paradise (Epimachus fastuosus).
They also recorded the "lost" Bird of Paradise -- Parotia berlepschi (known as Berlepsch's six-wired bird of paradise), and the newly described wattled smoky honeyeater (Melipotes carolae), both known only from the Foja Mountains.
The Indonesian Government has declared the region a National Wildlife Sanctuary, and CI continues to work with the government and local communities to build on this conservation success and ensure even greater protection of the area. As the global community searches for solutions to climate change, large untouched forested areas such as these will become more and more valuable as essential carbon sinks.
The cutting and burning of tropical forests worldwide emits at least 20 percent of total global greenhouse gases. Protecting these forests minimizes the impact of climate change while providing direct benefits to local populations, such as fresh water, clean air, food, seed dispersal, pollination and sources of medicines.
*Conservation International (CI) and Indonesia Institute of Science (LIPI) scientists were accompanied by the first film crew to obtain footage of the region and its wildlife on an expedition to the Fojas in June 2007. A National Geographic photographer/scientist and a CBS News camera crew joined the team as they returned to the mountains. CI and LIPI scientists discovered dozens of new plants and animals on their first expedition to the region in late 2005. An account of the 2007 expedition was aired on the CBS News program, "60 Minutes" on Dec. 16.
"It's comforting to know that there is a place on earth so isolated that it remains the absolute realm of wild nature," said CI Vice President Bruce Beehler, who led the expedition. "We were pleased to see that this little piece of Eden remains as pristine and enchanting as it was when we first visited."
CI and LIPI plan another expedition back to the Foja Mountains in late 2008 or 2009. This proposed expedition will seek to survey the summit forests of the highest peak, and the little-studied lower montane elevations. They expect to find additional new species of frogs, mammals, butterflies, and plants.
Adapted from materials provided by Conservation International.

Fausto Intilla

www.oloscience.com

Penguins In Peril As Climate Warms

Source:

http://www.sciencedaily.com/releases/2007/12/071213203604.htm

ScienceDaily (Dec. 15, 2007) — The penguin population of Antarctica is under pressure from global warming, according to a WWF report.

The report, Antarctic Penguins and Climate Change, shows that the four populations of penguins that breed on the Antarctic continent — Adélie, Emperor, Chinstrap and Gentoo — are under escalating pressure. For some, global warming is taking away precious ground on which penguins raise their young. For others, food has become increasingly scarce because of warming in conjunction with overfishing.
"The Antarctic penguins already have a long march behind them," says Anna Reynolds, Deputy Director of WWF’s Global Climate Change Programme.
"Now it seems these icons of the Antarctic will have to face an extremely tough battle to adapt to the unprecedented rate of climate change."
The Antarctic Peninsula is warming five times faster than the average rate of global warming. The vast Southern Ocean has warmed all the way down to a depth of 3000m.
Sea ice — ice that forms from sea water — covers 40% less area than it did 26 years ago off the West Antarctic Peninsula. This decrease has led to reduced numbers of krill, the main source of food for chinstrap penguins. The number of Chinstraps decreased by as much as 30% to 66% in some colonies, as less food has made it more difficult for the young to survive. It's the same story for Gentoo penguins, who are increasingly dependent on the declining krill stocks as overfishing kills off their usual food sources.
The Emperor penguin, the largest and most majestic penguin in the world, has seen some of its colonies halved in size over the past half century. Warmer winter temperatures and stronger winds mean that the penguins have to raise their chicks on increasingly thinner sea ice. For many years, sea ice has broken off early and many eggs and chicks have been blown away before they were ready to survive on their own.
In the northwestern coast of the Antarctic Peninsula, where warming has been the most dramatic, populations of Adélie penguins have dropped by 65% over the past 25 years. Not only has food become scarcer with the disappearance of sea ice, but the Adélies’ warm-loving cousins, the Gentoos and Chinstraps, have also "invaded" the region.
Warmer temperatures mean that the atmosphere can hold more moisture, which in turn brings more snow. Scientists are worried for the Adélie penguin, which needs land that is free of snow and ice to raise their young, and is likely to lose out to its warm-loving cousins.
"The food web of Antarctica, and thus the survival of penguins and many other species, is bound up in the future of the sea ice," says Jame Leape, Director-General of WWF International.
"After such a long march to Bali, ministers must now commit to sharp reductions in carbon emissions for industrialized countries, to protect Antarctica and safeguard the health of the planet."
Adapted from materials provided by World Wildlife Fund.

Fausto Intilla

www.oloscience.com

Present-day Species Of Piranha Resulted From Marine Incursion Into Amazon Basin

Source:

http://www.sciencedaily.com/releases/2007/12/071203131505.htm

ScienceDaily (Dec. 14, 2007) — Piranhas inhabit exclusively the fresh waters of South America. Their geographical distribution extends from the Orinoco River basin (Venezuela) to the North, down to that of the Paraná (Argentina) to the South. Over this whole area, which also embraces the entire Amazon Basin, biologists have recorded 28 carnivorous species of these fish (2). In spite of the evolutionary success of this subfamily of fish, the mechanisms that generated the species richness of this group are still insufficiently known.

A team from the IRD, working in partnership with Bolivian and Peruvian scientists, aimed to establish how these species were able to evolve over the past 15 million years. They consequently took samples from around their whole distribution range. Between September 2002 and June 2003, numerous specimens of piranhas were collected from the Bolivian part of the Amazon. Complementary sampling was then conducted in the Brazilian and Peruvian sectors, from the Orinoco in Venezuela, and the São Francisco and the Paraná-Paraguay in Brazil. The team selected 57 specimens representative of 21 different species of piranhas, from 15 collection points distributed over the whole South-American hydrographic network,.
Mitochondrial DNA (mtDNA) of piranhas has a particularly high mutation rate and thus could be used as a molecular basis for reconstructing the evolution of the present-day species which are different yet very close to one another. These techniques using mtDNA sequences led to the conclusion that the origin of the piranha species inhabiting the rivers of South America today dates back to some ancestor at only a few million years B.P. Yet dating from fossils, whose morphologies are strikingly similar to those of present-day piranhas, strongly suggests that this fish subfamily already existed in South America's hydrographic system 25 million years ago. The modern species must therefore stem from a recent diversification.
Further investigation involving the construction of a phylogenetic tree by categorizing the study's 21 species allowed phylogenetic relationships between each of them to be established in order to test alternative hypotheses for the diversification that occurred over time. Examination of these data alongside geological-scale changes that have affected aquatic ecosystems with time brought out evidence that marine incursions played a fundamental role in the appearance then the distribution of piranha species. Five million years ago, the Atlantic Ocean advanced, its waters finding their way far onto the Amazon flood plain. The saline water invaded the lowland expanse of the great river and penetrated its tributaries situated below 100 metres of altitude, provoking the disappearance of many species of freshwater fish. Some of these would nevertheless have succeeded in finding refuge at high altitude, in particular in rivers that flowed on the Guianan and Brazilian shields.
DNA analysis confirmed this hypothesis and showed that the piranha populations present in the Amazon flood plain but situated 100 metres above sea-level have been in existence for no more than 3 million years. Hitherto, certain specialists had suggested that the present-day piranha species had arisen in the lower sections of the great rivers of South America. The scientists thought that from centres of speciation, piranhas would subsequently have dispersed to colonize the more upstream reaches of the river system. However, the results of the study give sustenance to another scenario.
According to that new hypothesis, during the marine incursion phase some piranha populations would have survived in the upstream parts of the network. Such populations would have differentiated into species--following the fragmentation of their zone of distribution, but probably also in response to ecological constraints specific to the basin where they were kept in isolation from each other. Once the ocean had regressed again, 3 million years ago, these piranhas could finally have dispersed downstream, finding their way back to the Amazon's lowland plain which would have served as a gathering ground for biodiversity. What now remains to be found are the ecological parameters that could have favoured the diversification of piranha populations so confined to the upper reaches of the river network.
One of the hypotheses advanced highlights water quality as a factor in stimulating ecological and morphological differentiation of species. The field survey observations indicated that some of the species were highly localized, in both geographical and ecological terms. For example, Serrasalmus hollandi is mostly found in turbid, sediment-laden waters flowing down from Andean mountain streams. In contrast, a new species the biologists discovered, lives in the same hydrographic basin but only in rivers with crystal-clear waters bearing very little sediment content.
However, water quality cannot be considered as the sole factor behind speciation, seeing that a third piranha species was found living in either of these two categories of river. The research results as a whole suggest that the superimposition of factors linked to geographical history and ecological conditions, intervening at different spatial and temporal scales, is responsible for the diversification of the piranhas. This is an evolutionary progression which should be transposable to other fish communities inhabiting South American waters.
(1) These investigations were conducted jointly with Institute of Molecular Biology and Biotechnology, University Mayor San Andrés, La Paz (UMSA - Bolivia), the Institute of Research on the Peruvian Amazon (IIAP - Peru) and the Laboratoire Génome, Populations, Interactions, Adaptation (GPIA) in Montpellier.
(2) Herbivore piranhas also exist. In 2003, IRD scientists described new impressively sized species caught in French Guiana. (See scientific bulletin n° 168)
Adapted from materials provided by Institut de Recherche Pour le Développement.

Fausto Intilla

www.oloscience.com

World's Most Endangered Gorilla Fights Back

Source:

http://www.sciencedaily.com/releases/2007/12/071205122539.htm

ScienceDaily (Dec. 11, 2007) — In the wake of a study that documented for the first time the use of weaponry by Cross River gorillas to ward off threats by humans, the Wildlife Conservation Society has announced new field surveys to better protect this most endangered great ape.

The study, published earlier this year in the Journal of Primatology, found several instances of gorillas throwing sticks and clumps of grass when threatened by people. Gorillas usually flee and rarely charge when encountered by humans.
Cross River gorillas are restricted to Nigeria and Cameroon. They number only around 300 individuals, making them the most endangered of the four gorilla sub-species.
The Wildlife Conservation Society, which has studied Cross River gorillas since 1999, will begin new field surveys next month in an attempt to catalogue all potential gorilla habitat.
Earlier this year, the Wildlife Conservation Society released an action plan to safeguard Cross River gorillas that included creating additional protected areas and raising awareness of this little known great ape. The observations of weapon-use took place in the proposed Kagwene Gorilla Sanctuary in Cameroon -- one of the new protected areas recommended in the report.
In 2005 the Wildlife Conservation Society documented the first case of tool use among gorillas when researchers discovered individuals using sticks to check the depth of streams before crossing them.
The surveys are being funded in part by the U.S. Fish and Wildlife Service.
Adapted from materials provided by Wildlife Conservation Society.

Fausto Intilla

www.oloscience.com

In Promiscuous Antelopes, The 'Battle Of The Sexes' Gets Flipped

Source:

http://www.sciencedaily.com/releases/2007/11/071129100050.htm

ScienceDaily (Dec. 3, 2007) — In some promiscuous species, sexual conflict runs in reverse, reveals a new study. Among African topi antelopes, females are the ones who aggressively pursue their mates, while males play hard to get.

The classical view of sexual conflict holds that males, for whom reproducing is cheap, will mate as much as possible. On the other hand, females, who must pay a heftier price, are choosier about their mating partners.
"When biologists talk about the 'Battle of the Sexes,' they often tacitly assume that the battle is between persistent males who always want to mate and females who don't," said Jakob Bro-Jørgensen of University of Jyväskylä in Finland. "However, in topi antelopes, where females are known to prefer to mate with males in the center of mating arenas, we've found a reversal of these stereotypic sex roles."
Such role reversals may occur in species where females benefit from mating multiply, either because it increases their chances of conception with high-quality males or simply because it increases the probability that they conceive at all, Bro-Jørgensen added. He noted that this reversed sexual conflict might not be a rarity in the animal kingdom, as topi are "in many ways a very typical mammalian species characterized by male mate competition and female choice."
In promiscuous species--those in which individuals mate with multiple partners within a short time period--Bro-Jørgensen's group suspected that females might sometimes have higher optimum mating rates than their mating partners. Topi antelope offered an ideal opportunity for studying the dynamics of sex roles in promiscuous mammals, Bro-Jørgensen said, because over a month and a half, individual females become receptive to mating for roughly one day, when they mate several times with each of about four males on average. Females prefer to mate with those males who have succeeded in acquiring territories in the center of "mating arenas," known as leks. But the majority of females also mate with other males as well, resulting in intense sperm competition.
Indeed, they have now shown that aggressive female topis compete with one another for a limited supply of sperm from the most desirable members of the opposite sex, even attacking their fellow mating pairs. Meanwhile, resistant males grow choosier about their mating partners, deliberately selecting the least mated females and launching counterattacks against aggressive females with whom they've already mated.
The bottom-line of the findings, according to Bro-Jørgensen: "We should not regard coyness as the only natural female sex role just as we should not expect that it is always the natural male sex role to mindlessly accept any mating partner," he said. "Nature favors a broader range of sex roles."
This research was published online on November 29th in Current Biology.
The researcher is Jakob Bro-Jørgensen, of the Department of Biological University of Jyva¨ skyla, Jyva¨ skyla¨, Finland; and the Institute of Zoology, Zoological Society, Regent's Park, London, UK.
Adapted from materials provided by Cell Press.

Fausto Intilla

www.oloscience.com