Evolution of Love Darts
Because of the presence of darts in many superfamilies of the Stylommatophora, it seems likely that love darts appeared during the early evolution of the Pulmonata, and that the ancestors of the Stylommatophora possessed darts already.
During evolution, darts appear to have been lost secondarily, i.e., after they had evolved and been functional. Vestigial darts (ones that exist only in a rudimentary condition) occur in the family Sagdidae., and in many Helicoidea, the surrounding organs have also degenerated (become non-functional). The sarcobelum is a fleshy or cuticle-coated papilla which is considered to be a degenerated, previously dart-bearing, organ.
Read more about this topic: Love Dart
Famous quotes containing the words evolution of, evolution, love and/or darts:
“Analyze theory-building how we will, we all must start in the middle. Our conceptual firsts are middle-sized, middle-distanced objects, and our introduction to them and to everything comes midway in the cultural evolution of the race.”
—Willard Van Orman Quine (b. 1908)
“Analyze theory-building how we will, we all must start in the middle. Our conceptual firsts are middle-sized, middle-distanced objects, and our introduction to them and to everything comes midway in the cultural evolution of the race.”
—Willard Van Orman Quine (b. 1908)
“In their sympathies, children feel nearer animals than adults. They frolic with animals, caress them, share with them feelings neither has words for. Have they ever stroked any adult with the love they bestow on a cat? Hugged any grownup with the ecstasy they feel when clasping a puppy?”
—Jessamyn West (1907–1984)
“Rejoice with the anchovy who darts in and out of salads.”
—Anne Sexton (1928–1974)