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Night vision is of lower quality than day vision because it is limited in resolution and colors cannot be discerned; only shades of gray are seen. [1] In order for humans to transition from day to night vision they must undergo a dark adaptation period of up to two hours [ 2 ] in which each eye adjusts from a high to a low luminescence "setting ...
The kiwi is a family of nocturnal birds endemic to New Zealand.. While it is difficult to say which came first, nocturnality or diurnality, a hypothesis in evolutionary biology, the nocturnal bottleneck theory, postulates that in the Mesozoic, many ancestors of modern-day mammals evolved nocturnal characteristics in order to avoid contact with the numerous diurnal predators. [3]
A Young Man Reading by Candlelight, Matthias Stom (ca. 1630). A night owl, evening person, or simply owl, is a person who tends or prefers to be active late at night and into the early morning, and to sleep and wake up later than is considered normal; night owls often work or engage in recreational activities late into the night (in some cases, until around dawn), and sleep until relatively ...
Melatonin, an indoleamine, is a natural compound produced by various organisms, including bacteria and eukaryotes. [1] Its discovery in 1958 by Aaron B. Lerner and colleagues stemmed from the isolation of a substance from the pineal gland of cows that could induce skin lightening in common frogs.
The typical height of an adult human is between 1.4 and 1.9 m (4 ft 7 in and 6 ft 3 in), although this varies significantly depending on sex, ethnic origin, and family bloodlines. [239] [240] Body size is partly determined by genes and is also significantly influenced by environmental factors such as diet, exercise, and sleep patterns. [241]
Before the introduction of image intensifiers, night glasses were the only method of night vision, and thus were widely utilized, especially at sea. Second World War era night glasses usually had a lens diameter of 56 mm or more with magnification of seven or eight. Major drawbacks of night glasses are their large size and weight.
The central dogma of molecular biology deals with the flow of genetic information within a biological system. It is often stated as "DNA makes RNA, and RNA makes protein", [1] although this is not its original meaning. It was first stated by Francis Crick in 1957, [2] [3] then published in 1958: [4] [5] The Central Dogma.
[139]: 153 Domestic cats are a major predator of wildlife in the United States, killing an estimated 1.3 to 4.0 billion birds and 6.3 to 22.3 billion mammals annually. [140] Certain species appear more susceptible than others; in one English village, for example, 30% of house sparrow mortality was linked to the domestic cat. [141]