More evolution news from a cluster of news published in the scientific journals in the last week
In a right turn - the right way
Southeast Asian snail-eating snakes have more teeth on the right side of their jaw (about 6 more teeth) than the left side of their jaw. why? What causes the asymmetry? This is probably related to their food. Most snails feed on right-handed (clockwise) shells, and hence the best way to attack and bite the snail's exposed body is from the right side, from the snake's point of view. The snakes were found to consume the snail longer when the treats were left-handed snails, which are rarer, the researchers report in the journal Biology Letters. It is possible that the adaptation of snakes to the right-handed rotation of the snail shells is one of the reasons for the wide variety of snail species with left-handed rotation of the shell in Southeast Asia.
(Photo: Masaki Hoso / Kyoto University)
glides easily
Maybe the track is slippery, but that's exactly how snails like it...
The mucus they secrete helps them avoid injury and even climb walls. But the best mucus is not from snails, but from someone else, according to a report in the journal Proceedings of the Royal Society B: Biological Sciences. The researchers found that when one snail follows the mucus path of another snail, it secretes only about a quarter of the amount of mucus it would normally produce. Because snails invest about a third of their resources in the production of mucus, those who surf the saliva tracks of their predecessors can save energy and devote it to other purposes.
(Photo: Mark Davies)
Stop, or I'll spit on you!
Silkworm larvae usually hide from predators by burrowing between the leaves, but when the hiding is revealed and they are exposed, they do not gnash their teeth and remain inactive. Instead these worms, which are bright and phosphorescent green in color, clench their serrated jaws back and forth and thus produce ticking sounds that warn the oncoming attackers. A report on this behavior appears in the Journal of Experimental Biology. When it is necessary, the larvae back up their warning with another means - they regurgitate a dark brown liquid. For birds and bats this digestive fluid is repulsive and salty, but so far it is not clear to researchers why and what in its composition deters the attackers.
(Photo, Video: Jayne Yack)
4 תגובות
Hindi poetry
Class A2
Hana
Thank you very much for the enriching information, but apparently we both did not understand the first topic in the first reading: in the second reading I noticed the speculation in the last line that explains the title - the connection is that as a result of the adaptation of the snakes to right-handed snails, a greater distribution of left-handed snails was created (according to the speculation) .
The connection is the arrangement of teeth in the snakes which developed only on one side to crack the shell of the snails. A snake with many teeth on the one hand gives it an evolutionary advantage in preying on snails.
Regarding the mucus of the snails and the clicking of the teeth of the silkworm, the evolutionary connection is tenuous.
And by the way what is most important, a common mistake was made here - the silkworm is not a worm because a worm will never turn into a (silky) butterfly.
Personal Knowledge
Sabdarmish Yehuda
What is the connection between the text and the title (and especially the word "evolutionary")?