Humans are the only animals to drink the milk from an other animal. All juvenile mammals can drink mother’s milk because they have the enzyme lactase to digest the milk. At a certain age however. the genome that makes the enzyme gets switched off and the animal is not able to digest milk anymore. This is the same in humans, except for a small population in North-West Europe in which at some point in history a genetic variation appeared, resulting in their ability to drink milk as adults. That means bad news for this Dutch male calf: he will not be drinking any of it’s mother milk and will be sent off to the butcher.
The modern English word green comes from the Middle English and Anglo-Saxon word grene, from the same Germanic root as the words “grass” and “grow” By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into energy.
Twilight is the time between dawn and sunrise, or between sunset and dusk. After sunset, some of the sunlight will still be visible until the sun has passed below 18 degrees of the horizon. During this time, rays of sunshine can still illuminate some of the higher parts of the evening sky, while clouds that are lower and aren’t reached by the sun will look black as night.
The flight of a seagull involves mechanics similar to those used in aviation. The angle at which the seagull’s wing approaches the air affects lift.The length of the wing also determines how much lift is made. Seagulls can increase their speed by stretching their wings out as much as possible thus making optimal use of the wind.
These cows living in the South of the Netherlands seem to have a royal stable for their living pleasure. However, a typical milk cow in the intensive farm industry is raised on a concrete slab in a stall barely bigger than its body. The animals never touch grass or see sun until the day they are herded to slaughter.
The yellow flowers of dandelions mature into blowballs that can each contain 50 - 200 seeds. The seeds are capable of travel over long distances, but 99% of seeds will land within 2 meters of the original flower, often resulting in dense stands of dandelions.
Tulips are an important product for Dutch export and the fields with flowers attract many foreign tourists. Originally however, tulips are not endemic to The Netherlands, they were introduced in the around 1590AD from Turkey. During the 1630’s tulips became so popular that at some time during ’ tulip mania’ the bulbs were literally worth their weight in gold.
Clogs or klompen are part of the stereotypical image of the Netherlands, along with tulips, cheese and windmills. Millions of pairs of these wooden shoes are sold in the Netherlands each year, the majority of them to tourists. Some Dutch farmers still wear their wooden shoes around the farm, upholding a tradition that dates back to the Middle Ages.
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