Do you know why having learnt how to tie shoelaces at the age of 2 we remember it for a lifetime, but we cannot recall our second birthday or other events of this time period? This happens due to the phenomenon called childhood amnesia and that’s the topic of this article. Continue reading
If walking down the street you come across a cat with black and red patches – be sure it is she. Nearly one hundred percent of calico cats is female. But why it’s so? To answer this question we need to involve a bit of genetics into consideration. Let’s see why male cats almost never happen to be triple colored.
Male and female cats’ coat color differs in case when genes that define coloring are located in sex chromosomes. The latter which were indicated as X and Y, define the forming of gender itself. Female cats, like all the other mammals, have 2 X-chromosomes (XX) whereas males have one X and one Y (XY). Continue reading
It’s Monday morning! Have you already taken your doze of coffee? Thinking of another cup, maybe? As it turns out, our genetics is blamed for addiction to coffee. Some people need to drink up to three cups of strong coffee, while just a latte will suffice for others. As new study shows, such a reaction to most popular drink is due to genetic variations. Continue reading
Once Russian field marshal Suvorov advised his soldiers to “keep their feet in warmth but head – in cold”. However, we tend to treat this quote skeptically and put on warm hats with ear-flaps in chilly weather. In fact, head takes on average 8.86% of body’s surface and 20.2% of convective heat loss. Blood vessels’ location and thermal-physical properties (an uneven surface of face) explain this high heat exchange and make us feel cold even in the warmest clothes. Nevertheless, the question is how to protect our heads from cold.
In 1980’s scientists worldwide made a paradoxic discovery: the head doesn’t need enhanced thermal isolation. Even the cloth cap can become a reliable barrier on the way of heat transfer. This outcome fuels useful practical recommendations: headwear should be appropriate to particular weather conditions, and not too warm at the same time. “Hot hat” is: Continue reading
Recently we’ve discussed why leaves are green. Now the summer is over and soon the trees will change colors. Do you know why leaves turn yellow in autumn? This article is devoted to color change of green plants with change of seasons.
Deciduous trees in the temperate zones change their colors in autumn. Being green in summer, they turn orange, yellow, purple, red or even brown. This transformation is triggered by day shortening in September. The photoreceptor phytochromereacts to the change in the length of the day. When the days are shortening, plants green pigment chlorophyll starts to break down. Chlorophyll destruction unmasks accessory pigments, e.g. carotenoids that have yellow-orange colors.
Big animals existing nowadays have a lot in common. Among other similarities, all of them tend to move slowly. You probably know that large animals like elephants, rhinos, etc. move slower than smaller ones like mice, for example. Of course, you might object that named species can move with considerable speeds and, say, elephant outruns human with no effort at all. That is so, but in average they do move pretty slow. In this section we’re going to discuss the reasons why it happens. Continue reading
Have you ever seen a lotus? If yes, you’ve probably noticed that its flowers are not only incredibly beautiful, but somehow stay clean even when the water around is muddy and dirty. Leaves and flowers are not wetted by water, so the droplets roll off them like balls of mercury, washing away all the dirt. Do you know why the leaves of this amazing plant possess self-cleaning property? This is called lotus effect and we’re going to discuss how it works.
