Neanderthals and modern humans were interbreeding much earlier than was previously thought, scientists say.
Traces of human DNA found in a Neanderthal genome suggest that we started mixing with our now-extinct relatives 100,000 years ago.
Previously it had been thought that the two species first encountered each other when modern humans left Africa, about 60,000 years ago.
Source: http://www.bbc.com/news/science-environment-35595661
Some scientists argue that human uniqueness is the result of two primary features: one, that we are a powerful species, and two, that we gained our power rapidly. In this clip from the 2015 World Science Festival program “Planet of the Humans: The Leap to the Top,” molecular biologist Paul Bingham attempts to account for both of these features through an approach known as “social coercion theory,” which posits that humans control the conflicts of interest among non-kin to engage in large-scale social cooperation.
Source: http://www.bbc.com/news/science-environment-31718336
Scientists have unearthed the jawbone of what they claim is one of the very first humans.
The 2.8 million-year-old specimen is 400,000 years older than researchers thought that our kind first emerged.
Link: http://www.bbc.com/earth/bespoke/story/20150123-earths-25-biggest-turning-points/index.html
Our planet has existed for 4.5 billion years, and it has been a busy few eons. Here are the 25 biggest milestones in Earth’s history. From leaps forward in evolution to devastating asteroid impacts, these were the turning points that shaped our world.
One of the evidence of evolution is vestigial organs. In this regard, appendix is one of the most often quoted example for humans. While exploring the subject of human appendix on Scientific American, I found the following articles:
“human appendix does appear to have originated at a time when primates ate plants exclusively, and all that fiber was tougher to digest.”
Loren G. Martin, professor of physiology at Oklahoma State University, says: “For years, the appendix was credited with very little physiological function. We now know, however, that the appendix serves an important role in the fetus and in young adults.”
A study in the Journal of Evolutionary Biology finds that many more animals have appendixes than was thought, and that the appendix is not merely a remnant of a digestive organ called the cecum. All of which means that the appendix might not be so useless. Steve Mirsky reports.
Thus, although scientists have long discounted the human appendix as a vestigial organ, there is a growing body of evidence indicating that the appendix does in fact have a significant function as a part of the body¿s immune system. The appendix may be particularly important early in life because it achieves its greatest development shortly after birth and then regresses with age…
You may have heard that the appendix is a relic of our past, like the hind leg bones of a whale. Bill Parker, a professor of surgery at the Duke University School of Medicine, heard that, too; he just disagrees. Parker thinks the appendix serves as a “nature reserve” for beneficial bacteria in our gut.
A study by James Grendell, chief of the division of Gastroenterology, Hepatology and Nutrition, at Winthrop University-Hospital shows that Individuals without an appendix were four times more likely to have a recurrence of Clostridium difficile, exactly as Parker’s hypothesis predicted. Recurrence in individuals with their appendix intact occurred in 11% of cases. Recurrence in individuals without their appendix occurred in 48% of cases.
