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They found that the dinosaur group directly related to birds shrank rapidly from about 200 million years ago.

Theropods shrunk 12 times from 163kg (25st 9lb) to 0.8kg (1.8lb), before becoming modern birds.

The researchers found theropods were the only dinosaurs to get continuously smaller.

From this analysis they produced a detailed family tree mapping out the transformation of theropods to their bird descendants.

It traces evolving adaptations and changing body size over time and across dinosaur branches.

The researchers concluded that the evolution of the branch of dinosaurs leading to birds was more innovative than other dinosaur lineages.

this sustained shrinking and accelerated evolution of smaller and smaller body size allowed the ancestors of birds to develop traits which helped them to cope much better than their less evolved dinosaur relatives.

The researchers believe that miniaturisation and the development of bird-like traits had a joint influence on the evolution of the dinosaurs into today's birds. Professor Michael Benton, from the University of Bristol's school of earth sciences, said: "This study means we can't see the origin of birds as a sudden or dramatic event, with a dinosaur becoming a powered flyer overnight. "The functions of each special feature of birds changed over time - feathers first for insulation, and later co-opted for flight; early reductions in body size perhaps for other reasons, and later they were small enough for powered flight; improvements in sense of sight and enlargement of brain - even a small improvement in these is advantageous. "So perhaps it's a long-term trend associated with deputation to a new set of habitats, in the trees, to avoid predation, and to exploit new food resources."

"Birds evolved through a unique phase of sustained miniaturisation in dinosaurs," Mr Lee said.

The subdivision of hours and minutes into 60 comes from the ancient Babylonians who had a predilection for using numbers to the base 60. For example, III II (using slightly different strokes) meant three times 60 plus two or 182.

"We have retained from the Babylonians not only hours and minutes divided into 60, but also their division of a circle into 360 parts or degrees," says Lomb.

While each country has (in broad terms) historically had distinct measurements for distance, weights etc the method of splitting the day into 24 hours, one hour into 60 mins and one minute into 60 seconds seems to be the only one in use, and indeed to me the only one I know of. This non-metric measurement of time is far from ideal, but what other comparably accurate methods have been used historically?

Why are there 24 hours in a day? No one really knows. However, the tradition goes back a long way. Take, for example, this quote from Encyclopedia Britannica:

Why are there 60 minutes in an hour and 60 seconds in a minute? Again, it is unclear. It is known, however, that Egyptians once used a calendar that had 12 30-day months, giving them 360 days. This is believed to be the reason why we now divide circles into 360 degrees. Dividing 360 by 6 gives you 60, and 60 is also a base number in the Babylonian math system.

What do a.m. and p.m. mean? These abbreviations stand for ante meridiem, before midday, and post meridiem, after midday, and they are a Roman invention. According to Daniel Boorstin in his book The Discoverers, this simple division of the day into two parts was the Romans' first increment of time within a day:

Crying may also have a biochemical purpose. It's believed to release stress hormones or toxins from the body, says Lauren Bylsma, a PhD student at the University of South Florida in Tampa, whose research has focused on crying.

Each rain droplet reflects all colors at a given point and time, but only one color comes back to your eye, requiring million of rain droplets to create a rainbow.  As the rain droplets fall through the sky, the colors of the spectrum being reflected and refracted are constantly changing.

The perfect time and place to look for a rainbow you need bright sunlight to your back and rain clouds off in the distance in the direction of your shadow. If it is later than 4:30 in the afternoon or earlier than 8:30 in the morning at these condition there is a very good chance you will be able to see a rainbow in the sky.  Other places you may see rainbows formed are fountains, in the ocean as the waves crash against the rock which create a mist in the air, waterfalls, sprinklers and mist from a garden hose. Always remember to have the sun at your back to see a rainbow, happy rainbow hunting!!!!!!

Rainbows form a complete circle, however only half is visible.  The horizon only  Picture from the web site of the Department of Physics and Astronomy, Arizona State University                                                             allows us to see half of the rainbow circle, so we see just an arc.  What causes the rainbow to have a circular formation is the way that rain droplets fall.  The rain droplets do not fall is flat sheet, however they tend to fall at various distances and speeds.  On some occasions you can see a full circle around a garden hose.

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SoaringSoaring flight is a special kind of glide in which the bird flies in a rising air current (called a thermal). Because the air is rising, the bird can maintain its height relative to the ground. The albatross uses this type of soaring to support its multi-year voyages at sea.