Curious Facts

Everything below is in the book — each fact links straight to the page it comes from.

1. The metre was almost defined by a honeybee. When France sought "an incontestable standard of measurement" for the new decimal system, Réaumur's first proposal was not a fraction of the earth's meridian but the worker bee's cell, whose dimensions are "so well calculated" that they seemed a fixed natural unit. Read it in the book →
2. A captive king cobra was fed an extra snake whenever a distinguished visitor called. "Ophi" the Hamadryad's ration was one ring-snake a week, but he was "occasionally required — and with no sacrifice of his principles either — to eat an extra snake to satisfy the curiosity of some distinguished visitor." Two small colubers were "not too much for his ten or twelve feet of appetite." Read it in the book →
3. A pony named Tinker was thought to have inherited the name of the man she killed. The white cayuse had at some point bucked off and killed a tradesman who mounted her against her will, "and thereby, as in the old Norse legends, she has inherited his strength, his wickedness, and his name." Read it in the book →
4. Honeycomb cells are tipped up four or five degrees so the honey cannot run out. Each hexagonal tube sits on a pyramidal base shared with three cells on the opposite face, and the whole array is angled: "so that the honey shall not trickle out as it would be likely to do if they were built strictly horizontal." Read it in the book →
5. Madagascan cattle were said to check the ground for a spider before lying down. Thomisus foka is "regarded with great terror by the natives, as being so poisonous that even its breath is deadly" — a dread inspired purely by its uncanny, crab-like, warty look. The spider is harmless; its rugose brown-and-red body simply mimics the fruit of the tree Hymenæa verrucosa. Read it in the book →
6. A fish that carries its eggs in a kangaroo pouch made of fused fins. In the female Solenostoma the lower pair of fins are "lightly joined at the edge, so as to form a sort of pouch like a kangaroo's," and she minds the fry after hatching too. The author's verdict on their prospects: "The most frequent adventure that happens to them on the way is, of course, being eaten." Read it in the book →
7. Darwin found a spider commune, in a family where the two sexes attack each other. Near St. Fe Bajada he saw black spiders with ruby marks whose vertical webs, two feet apart, were all hitched to enormously long common lines that "extended to all parts of the community." He calls this sociability "a very singular fact" in a genus of animals "so bloodthirsty and solitary that even the two sexes attack each other." Read it in the book →
8. Forest paths in Brazil were "barricaded" by webs of a spider reputed to catch birds. Darwin found every path blocked by strong yellow webs of a relative of Epeira clavipes — the species Sloane had claimed made webs in the West Indies "so strong as to catch birds." Read it in the book →
9. Bees build their comb hanging from living chains of their own bodies. The first arrivals hook onto the roof of the hive by the claws of their hind legs and the rest hang from them, so that "long chains are formed which serve as bridges for the ever mounting crowd to pass over." The chains multiply into garlands and finally a thick inverted cone of bees. Read it in the book →
10. The oriole was convicted of grape-stealing purely on circumstantial evidence. Caterpillars and injurious beetles made up ninety-six per cent of the stomach contents examined, yet grapes were charged to the bird only "presumably by this bird, since he has so frequently been found in the vineyard and must be the culprit." The author adds that the oriole belongs to the same family as "some generally accepted 'rascals'." Read it in the book →
11. Sand-wasps take bearings on their burrow before flying off, like a man memorising a spot. Bates watched wasps at Santarem circle their hole in the sand a few times before departing, "apparently to mark well the position of the burrow." He argued the instinct is "no mysterious and unintelligible agent, but a mental process in each individual differing from the same in man only by its unerring certainty." Read it in the book →
12. The umbrella bird can pull a feather parasol over its own beak. Wallace describes a crest of thickly set feathers over two inches long that can lie flat and invisible, or be spread into a hemi-ellipsoidal dome "completely covering the head, and even reaching beyond the point of the beak," the individual plumes standing out like dandelion seeds. Read it in the book →
13. Darwin measured earthworms by tracking a field of lime buried since 1827. To learn how much soil worms bring to the surface, he judged "the rate at which objects left on the surface are buried": quick-lime spread thickly on unploughed pasture at Maer Hall in about 1827 was dug up ten years later as a distinct buried layer. Read it in the book →
14. A spider painted with fake curling lichen edges — and it hunts instead of trapping. Epeira prompta is bluish-green like tree-trunk lichen, and "the bluish color is broken by waving black lines which imitate the curling edges of the lichens." In captivity it built no web at all, merely lines to run on, and leapt on gnats, flies and even a jumping spider — "a curious habit to be acquired by an Epeirid." Read it in the book →
15. The male stickleback glues his nest together with mucus from his own body. He weaves water-weeds round a fixed support and cements the straws with "gummy mortar" of secreted mucous threads, then goes courting: "his wedding-garment becomes even more brilliant and glancing than ever; he gleams in silver and changeful gems." Read it in the book →
16. A fish named for its ears. The long-eared sunfish carries a blackish membrane behind each cheek, "an 'ear-flap,' which in this species is longer than in any other of the sun-fish family, whence the specific name, megalotis," from the Greek for "great" and "ear." Read it in the book →