A Cambridge team says the creature owes its existence to a genetic quirk that offers some recompense for its prolonged celibacy.

Many asexual organisms have died out because they cannot adapt to changes in the natural world.

But an evolutionary trick allows this pond-dweller to survive when conditions change, researchers report in Science.

The secret to this novel survival mechanism lies in a twist of asexual reproduction, whereby the animal is able to make two separate proteins from two different copies of a key gene.

Prolonged celibacy

Dr Alan Tunnacliffe, from the Institute of Biotechnology at the University of Cambridge, who led the research, said his team had been able to show for the first time that gene copies in asexual animals can have different functions.

"It's particularly exciting that we've found different, but complementary, functions in genes which help bdelloid rotifers survive desiccation," he explained.

"Evolution of gene function in this way can't happen in sexual organisms, which means there could be some benefit to millions of years without sex after all."

The researchers discovered that two copies of a particular gene, known as LEA, in the asexual pond-dweller are different - giving rise to proteins with separate functions that protect the animal during dehydration.

One copy stops other essential protein molecules from clumping together as the animal dries out, while the second copy helps to maintain the fragile membranes that surround the creature's cells.

Genetic diversity

Humans and most other types of organism reproduce sexually. The union of sperm and eggs results in two copies (or a pair) of genetic instructions within a cell, one copy inherited from each parent.

This produces two nearly identical copies of each gene in each cell, and therefore two nearly identical proteins.

The "re-shuffling" of genetic material over many generations allows sexual animals to adapt to changes in their natural environment.

In contrast, many asexual organisms have died out because their rigid genetic make-up means they are unable to adapt in this way.

The latest discovery explains why the bdelloids have likely escaped this fate with their mechanism for generating genetic diversity in the absence of sexual reproduction.

The study reported in Science magazine was conducted on a species of bdelloid rotifer known as Adineta ricciae.

Source:

http://news.bbc.co.uk/2/hi/science/nature/7039478.stm

Ladybirds are voracious eaters of aphids

The ladybirds, from the foothills of the Sierra Nevada in the western United States, will eat pests on the newly-landscaped Manhattan property.

The bugs can eat 50 aphids a day, and will lay more larvae in due course.

"They'll do their thing out there!" said Eric Vinje, whose company Planet Natural supplied the ladybirds.

The ladybirds, Hippodamia convergens, were scattered across the grounds of Stuyvesant Town and Peter Cooper Village on Manhattan's Lower East Side as an alternative to using chemical pesticides.

"In most cases, we reach for a can of pesticide - and we kill not only the 'bad guys,' but the 'good guys'," Mr Vinje told the Associated Press news agency.

"All we're doing here is putting more of the 'good guys' to tip the scale, to get some kind of pest population control."

After being collected in Oregon, California and Montana, the ladybirds are chilled to a semi-dormant state, until they are shipped to purchasers.

When they arrived in Manhattan, "they were lively and ready to eat anything that was not too quick for them," Mr Vinje said.

Local residents need not worry about the ladybirds swarming or infesting homes, Mr Vinje says, as this is not the aggressive Asian ladybird Harmonia axyridis.

Source:

http://news.bbc.co.uk/2/hi/americas/7054892.stm

The fruit belonged to Joseph Roberts who was injured in an explosion at a Stoke-on-Trent colliery in 1891.

Here is more:

http://news.bbc.co.uk/2/hi/uk_news/england/staffordshire/7068974.stm

The medieval bishops, who died between 1200-1360, were discovered during an excavation at Whithorn Priory in Galloway between 1957-67.

Here is more: http://news.bbc.co.uk/2/hi/uk_news/scotland/south_of_scotland/7146828.stm