Curiosity corner: The tale of two kiwis — bird and fruit linked by looks
Question: Are the kiwi bird and the kiwi fruit related?
Reply: Well, not really. You don’t usually cross a bird with a fruit. However, there is a correlation, or perhaps a resemblance. The one kiwi is a flightless, nocturnal bird found only in New Zealand. Named for their cry, they are brownish or grayish in color with hairlike plumage. Kiwis are about a foot tall and weigh on the order of 5 pounds. They have slender bills and minute wings, but no external tail.
The other kiwi (fruit) grows on a grapelike vine and is native to south central China. Sometimes known as a Chinese gooseberry, the kiwi is a small, round fruit with fuzzy greenish brown skin that roughly resembles the plumage of the kiwi bird. The fruit was brought to New Zealand in the early 1900s, and this country is now a major producer. I suppose the fruit’s resemblance to the bird is how it got its name.
Question: Are all fish cold-blooded?
Reply: For the most part, yes. But, there are a couple of exceptions. Cold-blooded means the body temperature of the creature varies with the external temperature. Warm bloods, like us, maintain a relatively constant body temperature irrespective of the surrounding temperature. There are some fish, tuna and the mackerel shark, that have body temperatures higher than that of the surrounding water. Hence, they are termed warm-bodied. Cold-blooded fish lose internal heat in the circulating blood to water passing through the gills, and the body temperature is usually within a degree of the surrounding water temperature. Tuna and mackerel sharks, however, have a system whereby internal heat in the warm blood going to the gills is transferred to the cold blood coming from the gills. As a result, yellowfin and skipjack tuna have body temperatures that can vary 10-20° F above the water temperature – so warm-bodied Their cousin the bluefin tuna might qualify as a warm-blooded, as opposed to warm-bodied, fish. The bluefin maintains a fairly constant body temperature, varying only a few degrees over a much wider range of water temperature. Ask Charlie, or any mermaid you happen to see. …
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C.P.S. (Curious Postscript): A compromise is an agreement whereby both parties get what neither of them wanted. -Anon
Curious about something? Send your questions to Dr. Jerry D. Wilson, Science Division, Lander University, Greenwood, SC, 29649, or for e-mail, firstname.lastname@example.org. Selected questions will appear in the Curiosity Corner. © JDW