Cracking your Knuckles will cause arthritis in later life!!

The cracking sound in the knuckles is caused by the bones moving apart and forming a gas bubble - the sound is the bubble bursting. It is quite common to hear someone warning a knuckle cracker that they will get arthritis, but the worst that can happen to a compulsive-cracker is that their fingers joints may weaken over time. Arthritis is caused by a variety of things (Such as crystal formations in the case of gout) - but knuckle cracking isn't one of them.

It won't Forget

Wild crows can recognize individual human faces and hold a grudge for years against people who have treated them badly. Scientists at the University of Washington donned a rubber caveman mask and then captured and ringed wild crows. If the crows were later approached by someone wearing the same mask, they loudly scolded the intruder. The crows' antipathy to the caveman mask has lasted more than three years, even though they have had no further bad experiences with people wearing it.

Going to extremes

On April 23, the Swift X- ray satellite witnessed a record-breaking gamma ray burst (G R B), a blast that signals the explosive death of a massive star. Swift saw 10 seconds of gamma rays followed by an X-ray after glow. Such afterglows occur because the star's gamma-ray jets plow through surrounding material that has star previoulst shed. As they barrel through, the gamma rays transfer energy to the material and cause it to radiate. After localizing its position with Swift, and then performing follow-up observations with multiple ground based observatories, scientists determined that the burst called GRB 0800423, occurred when the universe was just one 630 million years old. (That corresponds to a red shift of 8.2)
The recorded red shift makes this GRB the most distant blast yet seen. The object's red shift corresponds to when the universe was just one-twentieth of its current age. Astronomers believethe first stars began forming around 200 million years after the Big bang, and GRB 090423's progenitor stars brings them closer to that time period.
It also gives astronomers clues about the little understood cosmic Dark Ages, and the following "reionization"epoch.

A Mammoth Discovery

An ivory carving provides evidence of Ice Age artisans. The little figurine
approximately half an inch long and weighing a fraction of an ounce-may not look like much, but at 35,000 years old, it's believed to be the oldest ivory carving ever found. Archaeologists recently unearthed the mammoth sculpture, along with four other Ice Age relics, in a cave in southwestern Germany. The pachyderm is impressively wrought and has a slim design and crosshatches on its feet. Scientists say it's among the earliest evidence of Ice Age artistry. Radiocarbon dating of the dig site's sediment places the sculpture at a point in time alongside the arrival of the first modern humans in Europe.