Males of some species develop bigger testes for competitive edge

Washington, Mar 24 (ANI): In species where competition for females is fierce, males have evolved bigger testes to beat their rivals, a new study has confirmed.

The study showed that testicle size matters in highly competitive animal societies, where females mate with many males or in which females live in groups ruled by an alpha male that must constantly defend his harem.

However, the females do not really seek out more endowed males. Instead, the rivalry occurs after mating, as sperm battle inside the female.

As expected, males with larger testes produce more sperm.

Males are generally known to have developed tricks for edging out their challengers, such as displaying brighter plumage—often seen in birds—or wooing females with gifts.

Testes size is part of this competition, according to study leader Carl Soulsbury, a biologist at the University of Bristol in the U.K.

Soulsbury said that evidence has also been found that within species, the biggest, most attractive, and healthiest males have the heftiest testes, which indicates that the two might have a link.

Previous studies had looked at testes size and mating behaviour, which could be unreliable, said Soulsbury.

Thus, he examined previously published data on several wild mammal species that used genetic testing to prove that litters of offspring had been sired by many males, or, in group-living species, that offspring had been sired by a single dominant male.

Then he used data on testes mass—as well as other factors, such as length of mating season—to develop a statistical model.

The model revealed that “where there”s a high competition between males, evolution has selected for larger testes,” said Soulsbury.

“It confirms what scientists have expected, but is the first to prove it using genetic data across a range of mammals,” National Geographic News quoted him as saying.

Men do not compete in the same way for women, meaning that their testes stay relatively small.

The study has been published in the journal PLoS ONE. (ANI)

Song birds have to deal with cover artists too

Washington, Sep 9 (ANI): Just like great singers among humans, birds too have to deal with cover artists who copy songs.

A new research has revealed that some bird species have evolved to sing the same tune as their rivals, in order to compete effectively.

Led by Dr. Joseph Tobias and Dr Nathalie Seddon from the Edward Grey Institute, University of Oxford, the research team analysed the calls and songs of two antbird species that were living side-by-side in the Amazon rainforest- the Peruvian warbling-antbird and the yellow-breasted warbling-antbird.

The study was aimed at investigating their similar songs, and, in particular, at testing the theory that the birds’ songs could become increasingly similar to enable effective communication between competing species.

The above notion has attracted controversy as many scientists have argued that convergence in territorial or mating signals results in needless confrontation or crossbreeding and the creation of hybrids.

“Biologists have long been fascinated by convergence in ecological traits as it offers tangible evidence of evolution and the forces of selection by which it operates, but until now there is no clear evidence that social competition between animal species can produce convergent signals. We examined this idea by analysing the structure and function of songs in two birds which we knew to be strong social competitors,” said Tobias.

The researchers studied the species in Peru and Bolivia at one site where they lived together, and two sites where they lived in isolation.

Firstly, they recorded three sets of signals-songs, calls, and plumage colour of both species (including a total of 504 songs from 150 individuals).

Later, they played them back to individuals of each species to test the significance of songs of both types.

The results showed that territorial songs of both species were extremely similar particularly where they lived together, such that territorial birds treated songs of both species as equally threatening.

In the meantime, they discovered that non-territorial signals like calls and plumage were highly divergent.

“In effect, the territorial songs of these birds are more or less interchangeable in design and function. Given that they last shared a common ancestor more than 3 million years ago, it is almost equivalent to humans and chimpanzees – which diverged around 5 million years ago – using the same language to settle disputes over resources” said Tobias.

“Our results provide the first compelling evidence that social interaction can cause convergent evolution in species competing for space and resources.

They also suggest that while competition drives convergence in territorial songs, this is offset by divergence in non-competitive signals such as plumage colour to promote species recognition and reduce the chance of interbreeding,” he added.

The study has been published in Evolution.(ANI)

World’s smallest parrot filmed in wild for first time

London, September 8 (ANI): The world’s smallest parrot, which is not much bigger than an adult person’s thumb, has been filmed in the wild for the first time.

According to a report by BBC News, an expedition team filming in Papua New Guinea for the BBC programme ‘Lost Land of the Volcano’ caught two of the buff-faced pygmy parrots on camera.

Another adult, which weighs less than half an ounce, was also trapped by the expedition team’s bird expert.

On average, buff-faced pygmy parrots (Micropsitta pusio) stand less than 9cm tall and weigh 11.5g (0.41oz).

They are found across the northern lowlands of the island of New Guinea from the west to the southeastern tip, up to an altitude of around 800m.

Males and females look similar, but females have less prominent markings on the head.

The birds have green feathers with yellowish plumage on their underparts; while their cheeks, face, and crown are more buff-coloured, hence their name.

BBC wildlife cameraman Gordon Buchanan first discovered a tiny nest belonging to two parrots deep within pristine rainforest.

The birds nest in termite mounds, using their beaks and claws to dig their way in before laying eggs in the hole created.

Buchanan staked out the nest from within a camouflaged hide, and was rewarded after a long wait when two birds returned.

He filmed the pair at their nest entrance, as the male and female reinforced their bond by rubbing against one another.

Later, another parrot was trapped unharmed by Dr Jack Dumbacher, an ornithologist from the California Academy of Sciences in San Francisco, US, who had accompanied the BBC expedition team.

Buff-faced pygmy parrots do not eat fruit and nuts but lichen and fungi.

However, so little is still known about their dietary habits that it has proved difficult to rear the birds in captivity. (ANI)

Soap-like foam produced by “red tide” algae caused American seabird deaths in 2007

Washington, Feb 21 (ANI): Intensive investigation by scientists has determined that a massive “red tide” bloom of marine algae had produced a foamy soap-like substance that stripped the natural waterproofing from the feathers of seabirds in the US, causing them to die in large numbers.

This massive die-off happened in late 2007, when hundreds of dead and stranded seabirds washed up on the shores of Monterey Bay, their feathers saturated with water and coated with an unknown substance.

“The problems we traditionally associate with harmful algal blooms are caused by toxins produced by the algae. In this case, it was a surfactant that removed the water-repellent properties of the feathers,” said Raphael Kudela, professor of ocean sciences at the University of California, Santa Cruz.

Although this red tide bloom was nontoxic, it was very harmful to the affected birds, which included grebes, loons, northern fulmars, and surf scoters.

Live birds found stranded on beaches around Monterey Bay were starving and severely hypothermic, having lost the insulation normally provided by their waterproof plumage.

A total of 550 birds were stranded alive and 207 were found dead during this event.

“There were a lot of questions at the time about whether the stranding was related to those events, and we were able to eliminate those possibilities,” Kudela said.

The dominant species in the red tide was a type of dinoflagellate known by the scientific name Akashiwo sanguinea, which has caused red tides in the past without harmful effects on wildlife.

Kudela said that the problems in 2007 resulted from the unusual combination of a large red tide late in the year, when large numbers of migrating birds had arrived in the area, plus big waves that churned up the water.

An algal protein produced the slimy foam that fouled the birds’ feathers. Its effects were similar to those of soap and other surfactants that are used in detergents to dissolve grease.

Wave action contributed to the problem by breaking up the cells of dying algae and churning the dissolved protein into the thick foam that was seen along the shoreline and floating on the surface of the water.

“We grew the algae in the lab, and when we shook it up it produced the same foam,” Kudela said. “The waves act like a blender, churning up the cells and the protein,” he added.

“Although 2007 was the first time we saw an impact on birds, the conditions are there for the same thing to happen the next time we have that combination of red tide, birds, and big storm waves,” he said. (ANI)

Soap-like foam produced by “red tide” algae caused American seabird deaths in 2007

Washington, Feb 21 (ANI): Intensive investigation by scientists has determined that a massive “red tide” bloom of marine algae had produced a foamy soap-like substance that stripped the natural waterproofing from the feathers of seabirds in the US, causing them to die in large numbers.

This massive die-off happened in late 2007, when hundreds of dead and stranded seabirds washed up on the shores of Monterey Bay, their feathers saturated with water and coated with an unknown substance.

“The problems we traditionally associate with harmful algal blooms are caused by toxins produced by the algae. In this case, it was a surfactant that removed the water-repellent properties of the feathers,” said Raphael Kudela, professor of ocean sciences at the University of California, Santa Cruz.

Although this red tide bloom was nontoxic, it was very harmful to the affected birds, which included grebes, loons, northern fulmars, and surf scoters.

Live birds found stranded on beaches around Monterey Bay were starving and severely hypothermic, having lost the insulation normally provided by their waterproof plumage.

A total of 550 birds were stranded alive and 207 were found dead during this event.

“There were a lot of questions at the time about whether the stranding was related to those events, and we were able to eliminate those possibilities,” Kudela said.

The dominant species in the red tide was a type of dinoflagellate known by the scientific name Akashiwo sanguinea, which has caused red tides in the past without harmful effects on wildlife.

Kudela said that the problems in 2007 resulted from the unusual combination of a large red tide late in the year, when large numbers of migrating birds had arrived in the area, plus big waves that churned up the water.

An algal protein produced the slimy foam that fouled the birds’ feathers. Its effects were similar to those of soap and other surfactants that are used in detergents to dissolve grease.

Wave action contributed to the problem by breaking up the cells of dying algae and churning the dissolved protein into the thick foam that was seen along the shoreline and floating on the surface of the water.

“We grew the algae in the lab, and when we shook it up it produced the same foam,” Kudela said. “The waves act like a blender, churning up the cells and the protein,” he added.

“Although 2007 was the first time we saw an impact on birds, the conditions are there for the same thing to happen the next time we have that combination of red tide, birds, and big storm waves,” he said. (ANI)

Soap-like foam produced by “red tide” algae caused American seabird deaths in 2007

Washington, Feb 21 (ANI): Intensive investigation by scientists has determined that a massive “red tide” bloom of marine algae had produced a foamy soap-like substance that stripped the natural waterproofing from the feathers of seabirds in the US, causing them to die in large numbers.

This massive die-off happened in late 2007, when hundreds of dead and stranded seabirds washed up on the shores of Monterey Bay, their feathers saturated with water and coated with an unknown substance.

“The problems we traditionally associate with harmful algal blooms are caused by toxins produced by the algae. In this case, it was a surfactant that removed the water-repellent properties of the feathers,” said Raphael Kudela, professor of ocean sciences at the University of California, Santa Cruz.

Although this red tide bloom was nontoxic, it was very harmful to the affected birds, which included grebes, loons, northern fulmars, and surf scoters.

Live birds found stranded on beaches around Monterey Bay were starving and severely hypothermic, having lost the insulation normally provided by their waterproof plumage.

A total of 550 birds were stranded alive and 207 were found dead during this event.

“There were a lot of questions at the time about whether the stranding was related to those events, and we were able to eliminate those possibilities,” Kudela said.

The dominant species in the red tide was a type of dinoflagellate known by the scientific name Akashiwo sanguinea, which has caused red tides in the past without harmful effects on wildlife.

Kudela said that the problems in 2007 resulted from the unusual combination of a large red tide late in the year, when large numbers of migrating birds had arrived in the area, plus big waves that churned up the water.

An algal protein produced the slimy foam that fouled the birds’ feathers. Its effects were similar to those of soap and other surfactants that are used in detergents to dissolve grease.

Wave action contributed to the problem by breaking up the cells of dying algae and churning the dissolved protein into the thick foam that was seen along the shoreline and floating on the surface of the water.

“We grew the algae in the lab, and when we shook it up it produced the same foam,” Kudela said. “The waves act like a blender, churning up the cells and the protein,” he added.

“Although 2007 was the first time we saw an impact on birds, the conditions are there for the same thing to happen the next time we have that combination of red tide, birds, and big storm waves,” he said. (ANI)

Soap-like foam produced by “red tide” algae caused American seabird deaths in 2007

Washington, Feb 21 (ANI): Intensive investigation by scientists has determined that a massive “red tide” bloom of marine algae had produced a foamy soap-like substance that stripped the natural waterproofing from the feathers of seabirds in the US, causing them to die in large numbers.

This massive die-off happened in late 2007, when hundreds of dead and stranded seabirds washed up on the shores of Monterey Bay, their feathers saturated with water and coated with an unknown substance.

“The problems we traditionally associate with harmful algal blooms are caused by toxins produced by the algae. In this case, it was a surfactant that removed the water-repellent properties of the feathers,” said Raphael Kudela, professor of ocean sciences at the University of California, Santa Cruz.

Although this red tide bloom was nontoxic, it was very harmful to the affected birds, which included grebes, loons, northern fulmars, and surf scoters.

Live birds found stranded on beaches around Monterey Bay were starving and severely hypothermic, having lost the insulation normally provided by their waterproof plumage.

A total of 550 birds were stranded alive and 207 were found dead during this event.

“There were a lot of questions at the time about whether the stranding was related to those events, and we were able to eliminate those possibilities,” Kudela said.

The dominant species in the red tide was a type of dinoflagellate known by the scientific name Akashiwo sanguinea, which has caused red tides in the past without harmful effects on wildlife.

Kudela said that the problems in 2007 resulted from the unusual combination of a large red tide late in the year, when large numbers of migrating birds had arrived in the area, plus big waves that churned up the water.

An algal protein produced the slimy foam that fouled the birds’ feathers. Its effects were similar to those of soap and other surfactants that are used in detergents to dissolve grease.

Wave action contributed to the problem by breaking up the cells of dying algae and churning the dissolved protein into the thick foam that was seen along the shoreline and floating on the surface of the water.

“We grew the algae in the lab, and when we shook it up it produced the same foam,” Kudela said. “The waves act like a blender, churning up the cells and the protein,” he added.

“Although 2007 was the first time we saw an impact on birds, the conditions are there for the same thing to happen the next time we have that combination of red tide, birds, and big storm waves,” he said. (ANI)

Soap-like foam produced by “red tide” algae caused American seabird deaths in 2007

Washington, Feb 21 (ANI): Intensive investigation by scientists has determined that a massive “red tide” bloom of marine algae had produced a foamy soap-like substance that stripped the natural waterproofing from the feathers of seabirds in the US, causing them to die in large numbers.

This massive die-off happened in late 2007, when hundreds of dead and stranded seabirds washed up on the shores of Monterey Bay, their feathers saturated with water and coated with an unknown substance.

“The problems we traditionally associate with harmful algal blooms are caused by toxins produced by the algae. In this case, it was a surfactant that removed the water-repellent properties of the feathers,” said Raphael Kudela, professor of ocean sciences at the University of California, Santa Cruz.

Although this red tide bloom was nontoxic, it was very harmful to the affected birds, which included grebes, loons, northern fulmars, and surf scoters.

Live birds found stranded on beaches around Monterey Bay were starving and severely hypothermic, having lost the insulation normally provided by their waterproof plumage.

A total of 550 birds were stranded alive and 207 were found dead during this event.

“There were a lot of questions at the time about whether the stranding was related to those events, and we were able to eliminate those possibilities,” Kudela said.

The dominant species in the red tide was a type of dinoflagellate known by the scientific name Akashiwo sanguinea, which has caused red tides in the past without harmful effects on wildlife.

Kudela said that the problems in 2007 resulted from the unusual combination of a large red tide late in the year, when large numbers of migrating birds had arrived in the area, plus big waves that churned up the water.

An algal protein produced the slimy foam that fouled the birds’ feathers. Its effects were similar to those of soap and other surfactants that are used in detergents to dissolve grease.

Wave action contributed to the problem by breaking up the cells of dying algae and churning the dissolved protein into the thick foam that was seen along the shoreline and floating on the surface of the water.

“We grew the algae in the lab, and when we shook it up it produced the same foam,” Kudela said. “The waves act like a blender, churning up the cells and the protein,” he added.

“Although 2007 was the first time we saw an impact on birds, the conditions are there for the same thing to happen the next time we have that combination of red tide, birds, and big storm waves,” he said. (ANI)