Men are on the road to extinction as their genes shrink and slowly fade away, a genetic expert warned today.

The researcher in human sex chromosomes said the male Y chromosome was dying and could one day run out.

However readers shouldn't worry just yet - the change is not due to take place for another five million years.

Professor Jennifer Graves revealed the bleak future to medical students at a public lecture at the Royal College of Surgeons (RCSI) in Ireland.

But all is not lost. She said men may follow the path of a type of rodent which still manages to reproduce despite not having the vital genes that make up the Y chromosome.

'You need a Y chromosome to be male,' said Prof Graves.

'Three hundred million years ago the Y chromosome had about 1,400 genes on it, and now it's only got 45 left, so at this rate we're going to run out of genes on the Y chromosome in about five million years.

'The Y chromosome is dying and the big question is what happens then.'

The male Y chromosome has a gene (SRY) which switches on the development of testis and pumps out male hormones that determine maleness.

In her lecture, entitled The Decline and Fall of the Y Chromosome and the Future of Men, Prof Graves discussed the disappearance of the Y chromosome and the implications for humans.

She said it was not known what would happen once the Y chromosome disappeared.
'Humans can't become parthenogenetic (asexual), like some lizards, because several vital genes must come from the male,' she continued.

'But the good news is that certain rodent species - the mole voles of Eastern Europe and the country rats of Japan - have no Y chromosome and no SRY gene.

'Yet there are still plenty of healthy male mole voles and country rats running around. Some other gene must have taken over the job and we'd like to know what that gene is.'

The scientist said there were several candidate genes which could take over from SRY, adding whichever one did take over was sheer chance.

'It is even possible that two or more different sex-determination systems based on different genes could arise in different populations,' she added.

'These could no longer reproduce with each other, leading to two different species of humans.'

The work of Prof Graves, of the Australian National University, Canberra, on the evolution of sex determination has paved the way for developments in diagnosis of gender disorders and gender-related disease in humans.

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Anaconda, a giant rubber "snake" that floats offshore and converts wave energy to electricity, is a step closer to commercialization. An 8-meter long, 1/25th scale version is currently undergoing tests in a large wave tank in Gosport, UK, and a full-size working version could be a reality in five years.

Harnessing the power of waves is an attractive proposition because they are much more energy dense than wind. But wave power remains the poor relation of the renewable energy sector due to the difficulties of cheaply operating machinery in the harsh marine environment. The world's first commercial wave farm only began operating last year, off the northern coast of Portugal.

A variety of other designs are in testing around the world, but none are as unusual as the Anaconda. The rubber snake is filled with freshwater – to help deter sea creatures from setting up a home inside – and sealed at both ends to create a semi-rigid balloon that floats at the sea's surface.

Wave pulse

The tube is anchored at one end and as waves wash along its length they exert pressure on the snake that is transmitted by the water inside. This forces Anaconda's walls to expand outwards into the wave troughs where they are under less pressure, forming "bulge waves" that travel along the Anaconda's length.

These waves are similar to those that pass through the human circulatory system and can be felt as the pulse in the wrist and neck, says Rod Rainey of Atkins Global, co-inventor of the Anaconda. When each bulge wave reaches the end of the snake it keeps a turbine spinning to generate electricity.

The snake is made from a rubber-based material similar to that used to make dracones – flexible containers that are filled with diesel or water and towed behind ships for quick and cheap transportation.

Other than the turbine, Anaconda has no moving parts and unlike other wave power devices it needs only one tether to the ocean floor. That lowers construction costs and reduces the need for maintenance – an expensive undertaking in offshore settings where corrosion and accessibility are problems, explains Rainey.

Des Crampton, CEO of Checkmate Seaenergy, the firm commercializing the flexible wave harvester, says a full-size Anaconda 200 meters long could generate enough energy to power 1000 average homes. "Anaconda captures more energy than all existing wave energy devices," he says.

Rainey and retired physicist Francis Farley began work on the concept in 2007, and tested mini Anacondas last year. The first full-size Anacondas could become operational in 2014.

from New Scientist …

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The dinosaurs were wiped out by volcanoes that erupted in India about sixty five million years ago, according to new research.

For the last thirty years scientists have believed a giant meteorite that struck Chicxulub in Mexico's Yucatan Peninsula was responsible for the mass extinction of species, including T Rex and its cousins.

But now Professor Gerta Keller says fossilized traces of plants and animals dug out of low lying hills at El Penon in northeastern Mexico show this event happened 300,000 years after the dinosaurs disappeared. Professor Keller said the meteorite, despite having a diameter spanning six miles, seems to have had no effect on any of the plant and animal life of the region whereas the volcano eruptions could have blocked sunlight, altered climate and caused acid rain. She said: 'Not a single species went extinct as a result of the Chicxulub impact.' research, which has taken twenty years, will stop the raging debate at the heart of the demise of the dinosaurs.

She said: 'The decades old controversy over the cause of the mass extinction will never achieve consensus.' Understanding what caused the dinosaurs to disappear remains a great mystery. Theories attempting to explain it include asteroid or cometary impacts, volcanoes, global climate change, rising sea levels and supernova explosions. Scientists know that at a point about 65 million years ago, some phenomenon triggered mass extinctions on the land and oceans.

Dr Richard Lane, of the US National Science Foundation's division of earth sciences which funded the research, said Prof Keller may be onto something. He said: 'Keller and colleagues continue to amass detailed stratigraphic information supporting new thinking about the Chicxulub impact and the mass extinction at the end of the Cretaceous. The two may not be linked after all.'

This has been always point of world wide debate … many people have spent years … sometimes their whole life just to find one single answer … HOW DID DINOSOURS REALLY DIED ?? … and , many scientists have their theories … asteroid hit … global warming … disease  … ice age … climate change … evolution … and now … the volcano … but nobody has never ever got confidence or say 100% reliable proof that their conclusion is correct … all theories are just based on assumptions … well , lets hope that someday … we will really able to know how those dinos disappeared suddenly all over the planet … because it can give us idea of future of mankind …

from DailyMail …

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