The white tail of a bunny is in sharp contrast with the rest of its camouflaged coat, but it serves an important purpose when the animal is being hunted. By focusing on the bright spot, a predator ignores the larger body of the animal. Then, when the rabbit executes a sharp turn, the spot disappears and the predator has to readjust to focus on the camouflaged coat, losing vital seconds.
In the city of Leiden many houses in the historic centre date back to the late Middle Ages, some even as far as 1300 AD. The warehouse pictured above dates back to 1574 and was stocked with grain that was transported over the adjacent canal.
In 2009 the National Institutes of Health and the U.S. Department of agriculture successfully mapped the bovine genome. They discovered that cattle have about 22,000 genes, of which 80% are shared with humans. This puts them right behind cats (90%) and chimpanzees (96-98%) in the ranking of animals that are genetically most similar to us.
Leaves of trees contain both chlorophyl -making them look green- and other pigments such as anthocyanins and carotenoids, which will give them a red, orange or yellow colour. As the amount of sunshine diminishes in fall, the production of chlorophyl decreases and the other pigments get their moment of glory, painting the forest in typical autumn colours.
The emblematic red and white mushroom is called the Amanita muscaria. It is mildly poisonous and eating it will result in psychoactive effects that are not considered desirable for recreational use. Indigenous peoples of eastern Siberia would avoid this problem by having a shaman eat the mushrooms and letting others drink his urine. This urine, still containing psychoactive elements, was more potent than the actual mushroom with fewer negative effects such as sweating and twitching.
One of the more interesting aspects of moss is that it can become very old. Some species of moss found on Antarctica are over 2.000 years old. Peet moss on the Hawaian Islands is even thought to be amongst the oldest multicellular organisms on Earth. This moss spreads by making copies of itself, meaning that a single plant has been alive and genetically unchanged for tens of thousands of years.
A recent study concluded that dogs can not feel complex emotions, like anger or guilt. However, unlike any other animal species, dogs are able to read and react appropriately to human body language such as gesturing and pointing, and they are able to understand human language to an extent greater than any other animal
Relative to other insects, dragonfly vision is extraordinarily good. The head consists almost entirely of two huge compound eyes, which gives the dragonfly nearly 360° vision. Each compound eye contains as many as 30,000 lenses, or ommatidia. A dragonfly uses about 80% of its brain to process all this visual information. They can see a wider spectrum of colors than humans.
The water droplets in storm clouds are much larger than those in normal clouds. They have smaller total surface areas relative to their volumes and scatter white light less intensely. Moreover, these larger water droplets absorb more light than the smaller droplets so the storm clouds look darker.
`Ram crayons` are wax blocks strapped to a ram’s chest. The ram leaves its mark on the sheep when it mates. The breeder can determine the lambing time and quota by the colour marking on the back of the sheep.
Sixteen is the fourth power of two. For this reason, 16 was used in weighing light objects in several cultures. The Chinese used to have 16 liangs in one jin. Chinese Taoists did finger computation counting the finger tips and joints of the fingers with the tip of the thumb. Each hand can count up to 16 in such manner.
The Wadden Sea is a tidal zone; some of the smaller uninhabited islands such as Rottumeroog can only be reached by taking a boat, waiting for the tide to drop and then walking the rest of the way over the mudflats. In order to navigate and reach the island safely, cut-off trees are placed to indicate to ships where the deeper parts are.
Unlike other bees who live in colonies with worker bees and a queen bee, sunflower bees are solitary and lay their own young in holes they excavate in the ground. Instead of making honey, they make “bee bread,” balls of pollen mixed with nectar, which they feed to their larvae.
Sempervivum tectorum or common houseleek is a species of flowering plant native to the mountains of southern Europe. It has been known since Roman times and its name tectorum means “of house roofs”; because the plant was thought to protect against thunderstorm it was often grown on rooftiles.
The family of swans that lives near my house had an uninvited visitor. At first the father swan tried to scare the intruder away by making a threatening posture and chasing him off. When this did not have the desired result he decided to take a good bite out the tail of his rival. That did the job.