Natures wonders: nursing amphibians (Introduction)

by David Turell , Friday, March 08, 2024, 17:46 (258 days ago) @ David Turell

The mother excretes a nourshing fluid:

https://mail.google.com/mail/u/0/#inbox/FMfcgzGxRxMdzcSKZMPfKLRFJBjpHVbb

"Nestled snug in their burrow, the young ones cuddle close to their mom. Here, she will care for her babies for months. When they’re hungry, they’ll grunt and suckle on her to alert her of their needs—and she will provide them with the nourishing, fatty fluid that fuels their growth. Life sure is rich and sweet for these young amphibians.

"Yes, you read that right: amphibians. The mom and babies referred to above are not mammals. They’re ringed caecilians (Siphonops annulatus): snake-like salamander relatives that independently evolved to excrete a milk-like substance to feed their young.

"Other amphibians, including a number of frogs, provide a lipid-packed, nutrient-rich fluid to their young while they’re still developing inside of them. But to date, no other amphibian species has been observed feeding already-birthed babies with such secretions.

“'This previously unobserved form of maternal provisioning challenges existing understanding of the evolution of parental care modes,” writes Marvalee Wake in a related Perspective. Many questions remain unanswered, like how is “milk” production triggered? What stimulates “lactation”? And what drove these animals to produce this milky substance in the first place? But integrative studies like this are inherently valuable, she says, as they deepen our understanding of evolution."

The original article:
https://www.science.org/content/article/watch-snakelike-creature-feed-milk-its-young?ut...

"Scientists studying the feeding behavior of caecilians—a group of limbless, egg-laying creatures—observed their offspring making a peculiar and rarely heard sound. They were clicking and chittering through their nasal cavities multiple times a day, seemingly begging for milk from their mothers (as seen in the video above). They even nibbled on her on occasion.

"As the researchers report today in Science, mom released a white substance from her cloaca, which her young immediately gobbled up.

"This “milk” comes from glands in caecilians’ fallopian tubes and is rich in fatty acids—three times richer, in fact, than cattle milk.

"Although only mammals produce true milk, the new study suggests this type of nursing is perhaps more common in the animal kingdom than previously thought."

Comment: just another example of convergence in evolution. Simon Conway Morris feels this is evidence of a designer.