Search results
Results from the WOW.Com Content Network
Aristotle's lantern in a sea urchin, viewed in lateral section. The mouth of most sea urchins is made up of five calcium carbonate teeth or plates, with a fleshy, tongue-like structure within. The entire chewing organ is known as Aristotle's lantern from Aristotle's description in his History of Animals (translated by D'Arcy Thompson):
[5] The green sea urchin has a structure called an Aristotle's lantern surrounding its mouth on its oral (under) surface. This has five teeth that can be used to rasp surfaces. It is largely herbivorous, feeding on the seagrass Thalassia. Its tube feet and spines also play a role in feeding, catching and holding bits of debris that float past. [4]
Aristotle’s lantern is a complex system of jaws and muscles which are capable of a variety of feeding types including suspension feeding, herbivory and detritivory feeding, and occasionally predation. Adaptations to this lantern have allowed sand dollars to live in habitats which have fine, shifting substrates.
It bridges the gap between the echinothurioids and the diadematioids. [5] The earliest crown group example was Echinothuria , which came from the Upper Cretaceous of southern England. Living members of the group were found after the Challenger expedition of 1872–76 began to explore the deep sea.
The works of Aristotle, sometimes referred to by modern scholars with the Latin phrase Corpus Aristotelicum, is the collection of Aristotle's works that have survived from antiquity. According to a distinction that originates with Aristotle himself, [ citation needed ] his writings are divisible into two groups: the " exoteric " and the ...
The sequence starts with a unary operation (the successor function with n = 0), and continues with the binary operations of addition (n = 1), multiplication (n = 2), exponentiation (n = 3), tetration (n = 4), pentation (n = 5), etc. Various notations have been used to represent hyperoperations.
Here 5 and 7 are fixed points of π, since π (5) = 5 and π (7)=7. It is typical, but not necessary, to not write the cycles of length one in such an expression. [ 1 ] Thus, π = (1 2 4 3)(6 8), would be an appropriate way to express this permutation.
The Isagoge (Greek: Εἰσαγωγή, Eisagōgḗ; / ˈ aɪ s ə ɡ oʊ dʒ iː /) or "Introduction" to Aristotle's "Categories", written by Porphyry in Greek and translated into Latin by Boethius, was the standard textbook on logic for at least a millennium after his death.