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Even in these modern days, when the lifespan of humans surpasses an all time record, women over 40 are generally believed too old to have babies, yet somehow there is no mention of the limit age men become less fertile at. If 40 looked like a rather young age to stop having children, a new study now shows that men ol... |
7 July 2008
05:08 GMT |
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Are men really tougher than women? Girls learn to read before boys do, get better marks in college, and even their brain contains more gray matter. Come to think of it, as early as in fetal state, males are medically weaker than females. The sex ratio at birth is slightly in favor of the boys. But in the womb, boys a... |
8 May 2008
14:06 GMT |
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1. The African ostrich (Struthio camelus) holds three records: it is the world's largest and fastest running living bird and lays the largest eggs. This bird can reach 160 kg (360 pounds) in weight and 2.75 m (9.2 ft) in height. Males are taller and heavier than females. Still, the African ostriches are not the ... |
6 May 2008
08:19 GMT |
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Radiation and chemotherapy employed for stopping cancers often put an end to the function of the ovaries, leading to early menopause, accompanied by osteoporosis, low sex drive and sterility. Nevertheless, a new technique of growing human eggs in the laboratory developed by a team at the Edinburgh University and repo... |
22 April 2008
16:36 GMT |
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A new organism develops inside the woman's womb due to the placenta, a special organ for delivering food and oxygen from the mother to the fetus. A new research made at the Stanford University School of Medicine and published in the journal Genome Research has revealed the first genetic clues about the ancient o... |
16 April 2008
04:00 GMT |
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No, toads do not cause warts (they are produced by viruses), nor scab, which is caused by a mite. But pet animals, like dogs and cats can transmit this parasite. Scabies is caused by the scab mite (Sarcoptes scabiei variety hominis), 0.3 to 0.9 mm long, which lives on the surface of the skin or beneath, feeding on de... |
14 April 2008
11:33 GMT |
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It is a vivid controversy: to eat or not to eat eggs. While a recent research has showed that consuming eggs reduces the risk of breast cancer in women by 24%, thanks to choline, a new one published in the American Journal of Clinical Nutrition reveals that middle-aged men who eat seven or more eggs hurry up to their... |
12 April 2008
04:30 GMT |
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You may associate eating too many eggs with health issues. But a new research to be published in The FASEB Journal shows the contrary. The dietary consumption of choline, an amine included in the group of vitamins B and considered an essential nutrient, abundant in eggs, has been found to decrease the risk of breast ... |
4 April 2008
14:06 GMT |
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This is a breakthrough in explaining egg fecundation and a research that could help us fight against many deadly bugs. A team made of researchers from UT Southwestern Medical Center and Imperial College London has described the basic gene mechanism of reproduction, in a research published online in the journal "Genes... |
31 March 2008
05:21 GMT |
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Over 15% of the couples in developed countries experience fertility issues. The last resort for women troubled by this is in vitro fertilization (IVF). But timing can be a big problem, as from holidays to work, all must be planned around the egg harvesting. A new research made at the Tel Aviv University and published... |
25 March 2008
14:06 GMT |
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You may depreciate creeping creatures like snakes and lizards, but the first mammals, the group which humans belong to, evolved from egg-laying reptiles. By feeding the young with milk, mammals skipped the yolk diet and the egg stage in their development. A new research published in the journal "PLoS Biology" has tra... |
19 March 2008
03:50 GMT |
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Female Komodo dragons do not need stem cell technology and genetic engineering to do it. They really can skip the male chapter in the case of breeding. Two Komodo dragons have hatched at the Sedgwick County Zoo, Wichita, Kansas, without the contribution of a male. These are the first dragons born by parthenogenesis i... |
11 February 2008
02:49 GMT |
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Your parents might urge you to get a job if you've reached 30 and you're still living with them, but in animals, this can be much tougher: dad will eat his offspring. A new research published in the journal "Biology Letters" has attempted to explain some of the reasons why parents might cannibalize their ow... |
7 February 2008
06:54 GMT |
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Everybody is now focusing on the British research forecasting male-free reproduction. The team at the University of Newcastle has achieved proto-sperms from human female bone marrow cells. Many already think of lesbian couples conceiving their own children, possessing DNA 100% coming from both women, not 50% from one... |
5 February 2008
14:06 GMT |
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Emu (Dromicaeus novaehollandiea) is represented on the emblem of Australia, being one of the Australians that cannot walk in "marche-arriere". This relative of the African ostrich can be 2 m (6.6 ft) tall (the second tallest living bird after the African ostrich) and weigh 35-50 kg (75-110 pounds), a third place amon... |
1 February 2008
14:06 GMT |
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When Europeans heard about it for the first time, they thought it was a legend. But the existence of the huge lizard whose skin could not be penetrated by bullets was real. The Komodo dragon (Varanus komodoensis) is the world largest living lizard: males can be up to 3 m (10 ft) long and weigh 150-200 kg (320-440 pou... |
29 January 2008
14:06 GMT |
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You already know this: the sex chromosome from your father dictated your sex: boy for Y, girl for X. It's the same case with all the mammals. The mother will always come with an X chromosome. But in reptiles, there are neither sex chromosomes, nor sex portions on the chromosomes. All the eggs have the potential ... |
24 January 2008
05:43 GMT |
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Well, Speedy Gonzalez might have been one of the cartoon heroes of your childhood, but mice are speedy in various aspects, including fertilization. A new research carried out at the University of Liverpool has discovered that field mice found a method of having very rapid fertilization that could also be connected t... |
24 January 2008
03:36 GMT |
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Typos are the source of many evil happenings all over the world, from wrong messages sent to wrong people, and continuously annoying people on the cell phone because you've remembered two numbers in the wrong order, up to changing the whole meaning of your essay's catchphrase to make it be the most obscene... |
21 December 2007
15:31 GMT |
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Sperm? That's simple: a cell with a flagellum that moves through a liquid called semen and attempts to fecundate an egg. Well, this is the human case, but nature can amaze you!1.Which are the performances of human sperm compared to our relatives? Humans, like animals, experience a fierce competition for sex. And... |
15 December 2007
07:20 GMT |
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The bee's universe is a tough monarchy, the proletariat has no say there. The queen honey bee decides the sex of her offspring, points a new research published in Behavioral Ecology, a finding that challenges the belief that queens are just 'egg laying machines' and that worker bees decide if the queen... |
19 November 2007
02:48 GMT |
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During a safari in the African, Australian or South American savannas you will come across some strange constructions resembling the towers of a castle. Their architects and builders are the termites, insects of the Isoptera order. They are also called "white ants", but have nothing to do with the real ants (which ar... |
17 November 2007
14:03 GMT |
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It is a reproductive paradox: giving birth to offspring just to eat them. But the behavior is widespread in many groups of animals, from bank voles and hedgehogs to house finches, wolf spiders and a lot of fish species. The paradox is increased by the fact that all these species are also very good parents for the res... |
15 November 2007
03:07 GMT |
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1. The largest crocodile species is saltwater crocodile (Crocodylus porosus), encountered from India to northern Australia and Fiji. In can reach 7 m (23 ft) in length and 1 tonne in weight! At 5 m (17 ft) length, it already has 0.5 tonne!Even so, a crocodile egg is no larger than that of a goose!The smallest crocodi... |
3 November 2007
08:06 GMT |
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We are a very odd species in many ways. For example, female animals too experience menopause and become sterile after a certain age, but this means a very close end to their lives. But women start releasing mature eggs at puberty age, and menstruation is installed at around the age of 13. By the age of 50, the egg re... |
1 November 2007
09:37 GMT |
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Garbage could be the solution for the future's fuel crisis. A team at Ohio State University has tried to figure out how to transform discarded chicken eggshells into an alternative energy source. The new technique employs eggshells to absorb carbon dioxide while delivering hydrogen fuel and could also lead to a ... |
3 October 2007
02:54 GMT |
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A woman is a complex universe. So complex, that 350 genes combine to allow her to become a mother. This is the number of genes found by a team at UT Southwestern Medical Center to be connected to female fertility, a breakthrough in the investigation of woman infertility. "This study gives us a way to begin to underst... |
25 September 2007
14:06 GMT |
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Unlike the present-day lizards, dinosaurs had a social behavior. And now the fossils of six young dinosaurs discovered together in a Chinese "nursery" reveal that these animals formed social groups much earlier than previously believed. "The find sheds light on the life of the beaked dinosaur Psittacosaurus and on th... |
20 September 2007
03:25 GMT |
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When a fish is known for its eggs rather than for the way it looks, this is a bad sign. There are 23 species of sturgeon fishes, assigned to 4 genera, all living in Northern Hemisphere, but if the name sturgeon sounds strange for many, caviar is linked by anybody to opulence. And this has been so since the ancient Ph... |
5 September 2007
16:56 GMT |
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Women already say that man is an appendix of the penis. As sex toys already replace the penis, only the sexual function remains. And when this will be gone, too, what will be men's fate? If amongst vertebrates, only sharks and some lizards have been known to reproduce without requiring sperm for fertilization, a... |
21 August 2007
14:06 GMT |
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As we all have learned, females produce eggs and males sperm. Females are the mothers and males are the fathers. This has been so ever since the beginning of times. The female takes care of the eggs and eventually of the offspring. And what if not? Nature has many surprises for us. Sometimes males are very devoted mo... |
14 August 2007
14:06 GMT |
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Sometimes, the war of the sexes can get out of control. Parents can abandon their offspring just to have a little more sex. Males for spreading their genes, and females to get more varied genes. In the case of the penduline tit (Remiz pendulinus), a European species, this could mean that one in three clutches of eggs... |
2 August 2007
08:44 GMT |
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These beasts made an elephant look like a mouse. Sauropod dinosaurs were big, but the titanosaurs were the biggest of all. Argentinosaurs, a South American titanosaur, was the largest and heaviest land animal ever. It lived in South America during the middle of the Cretaceous Period (around 100 million years ago). Ar... |
31 July 2007
04:53 GMT |
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Sex and economics seem to be connected: animals tend to invest in their offspring according to their expected payoff. A team of behavioral ecologists at the National Museum of Natural History and the Laboratory of Evolutive Parasitology, Paris showed that, in the peafowl (Pavo cristatus), when females mated with att... |
23 July 2007
04:55 GMT |
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This living fossil was thought to have been extinct. Till recently, an expedition on Papua's Cyclops Mountains revealed that the egg-laying mammal, baptized after the famous TV naturalist Sir David Attenborough, is still alive, as proven by burrows and tracks. Attenborough's long-beaked echidna is known to ... |
17 July 2007
07:17 GMT |
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Till now, it was real only in the science fiction movies. Now it's a fact: the first child has been born from a lab matured, frozen, thawed and then fertilized egg. In Canada. Three other moms are pregnant due to the same method. This special healthy baby girl was brought to life by one of 20 patients with polyc... |
3 July 2007
03:37 GMT |
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If your white wife gives birth to a Black child in Africa or a Mongoloid one in China, you wouldn't be very pleased. But there are mothers that change the coloration of their offspring according to the local environment. A team at the University of California, Santa Cruz, has discovered that female side-blotche... |
13 June 2007
09:16 GMT |
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It is clear that stem cells research could boom the medical advance. Currently stem cells are extracted from human embryos, but there is a major ethical issue around this theme: the stem cells' extraction destroys the embryos. In US, this type of research does not receive federal funds. Ian Wilmut, famous for cl... |
13 June 2007
03:30 GMT |
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You may expect that compensation rates for males which donate sperm would be significantly lower than for women donating eggs, but a recent investigation made by UCLA Sociologist Rene Almeling revealed discrepancies that cannot be explained by either market forces or the biological differences, defying the basic law ... |
25 May 2007
17:06 GMT |
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The common concept on female fertility states that at birth females have all their eggs inside their undeveloped (yet) ovaries and these eggs are released one by one (sometimes more than one) at each ovulation. At menopause, the ovaries are deserted by any egg. But in 2004 a Harvard team led by reproductive endocrino... |
23 May 2007
17:06 GMT |
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Humans employ modern technology to completely manipulate their reproduction: from in vitro fertilization to the sex determination of the embryo in just 6 weeks after fertilization. Perhaps the next "fashion" will be freezing eggs for future implantation, enabling women to postpone pregnancy as much as possible (ther... |
16 May 2007
08:34 GMT |
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You may think that only human males know when an offspring is not theirs (even if in practice, many do not grow their own children and this unwittingly...). It is known that in many mammals, when a male takes over a group of females, first he kills the offspring which of course, does not carry his genes (examples are... |
25 April 2007
07:26 GMT |
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It's easy to blame it on the woman, but in 15 % of cases, the guilt can be attributed to the stud. Now Cornell study could bring more hope for these couples, as a research team detected a gene mutation that induces male infertility in mice. This is the first dominant mutation found to specifically trigger infert... |
11 April 2007
04:18 GMT |
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The scientific world is shocked by the world's only known case of "semi-identical" twins. Signaled by journals Nature and Human Genetics, this American case (whose exact location has not been revealed) is of a twin pair identical on their mother's side, but sharing only half their genes on their father'... |
27 March 2007
07:02 GMT |
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Eggs are regarded as some of the most fragile things in nature. But when African ostrich eggs were tested, they supported a pressure of 120 kg!Of course, they are the largest eggs: 4.3- 6.4 pounds (or 1.5-2 kg of which 280 g are represented by the shell) and equals some 36 chicken eggs. Crocodiles, even if they can r... |
20 March 2007
11:06 GMT |
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Women resorting to IVF (in vitro fertilization) take drugs to boost egg maturation in their ovaries. These ovules are extracted by doctors and fertilized in the laboratory; but some women's ovaries cannot generate any egg even under medication, and in such cases the treatment fails. As IVF treatment means $10,00... |
15 March 2007
08:33 GMT |
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Scientists have been puzzled for long by the ability of the marine turtles to return their entire life to the same beach to depose their eggs. These egg-laying sites can be often located far from the feeding areas and the individuals (both females and males, as they mate in the same area where the females lay their e... |
8 March 2007
07:21 GMT |
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