Evolution

A new species of hominid thought to bridge the gap between prehistoric and modern humans has been found.The skeleton of a child dating back 2 million years is to be unveiled next week, the find represents an intermediary stage of human evolution that will fill in some of the gapsbetween our prehistoric ancestors and the first modern humans.

The new species of hominid, the evolutionary branch of primates that includes humans, is to be revealed when the two-million-year-old skeleton of a child is unveiled this week.

View: Full article | Source: Telegraph

Men may have a weaker immune system and could be more vulnerable to so-called 'man flu', scientists propose. Evolutionary factors and hormonal differences may make males more susceptible to infection than females, says a Cambridge University team. Their theory, outlined in a scientific journal, suggests there is a trade-off between a strong immune system and reproductive success. But a leading flu expert says there is no difference in men's immunity. Previous experiments have found differences in the ability of females and males to deal with infection.

Across a range of animal species, males tend to be the 'weaker sex' in terms of immune defences, says the Cambridge team. This is usually explained by the difference in hormones. High testosterone levels, they say, lead to more coughs and colds. The study, published in Proceedings of the Royal Society B journal, investigated the reason for these differences. Dr Olivier Restif, one of the authors, said: "If you assume that males are more exposed to infection, then can natural selection influence that process?" To find out, scientists developed a mathematical model that highlighted the role of other factors, like ecology and epidemiology, in shaping the immune systems of men and women. "If males are more exposed to infection than females (for behavioural reasons for example), it is possible to see them evolve lower immuno-competence than females," the authors wrote.

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A finger bone found in Siberia has revealed the DNA of a completely new type of human from 40,000 years ago.The find means that we now know of four seperate human species from around that time including neanderthals, modern humans and the recently discovered "hobbits" on the Indian islandof Flores.

A previously unknown type of ancient human, who lived about 40,000 years ago, has been identified using DNA from a finger bone found in Siberia. The extraordinary find brings to four the number of human species thought to have roamed the earth at that time.

View: Full article | Source: Sydney MorningHerald

The new discovery of stone tools on the island of Flores suggests an evolutionary history of over 1 million years.Homo floresiensis has continued to divide scientists the world over, now it is believed that their evolutionary history could stretch back 200,000 years more thanwhat was previously thought.

Newfound stone tools suggest the evolutionary history of the "hobbits" on the Indonesian island of Flores stretches back a million years, a new study says—200,000 years longer than previously thought.

View: Full article | Source: NationalGeographic