offspring
dr. dolittle | September 1, 2015Answer: pregnancy.
Unlike most animals, it is the male seahorses that give birth to live young. A new study conducted at the University of Sydney and published in Molecular Biology and Evolution, found that the male seahorses not only carry out the pregnancy, they also supply nutrients to the developing embryos, including fats and calcium. The researchers suspect that these nutrients are secreted into the brood pouch where they can be absorbed by developing embryos. According to quote from study author Dr. Whittington, published in the International Business Times, "Seahorse babies get a lot…
dr. dolittle | August 14, 2012
Studies of guppies show that bigger brains may mean "smarter" fish, but less offspring. Credit: Marrabbio2/Creative Commons
...at least for guppies. Dr. Alexander Kotrschal and colleagues at Uppsala University (Sweden) either shrank or grew the brains of guppies over multiple generations to create animals with up to 8-10% variations in brain size. To test for "smartness" they had the fish count by training the animals to look for food where a card with two or four symbols was shown. According to the researchers, the animals with larger brains tended to learn the task, whereas those with…
laelaps | March 19, 2010
At almost every aquarium I have ever visited with a seahorse exhibit, the plaque in front of the tank says the same thing: in seahorses and their relatives, males, not females, carry the babies. It is always interesting to watch the reactions of visitors to this curious fact. Adult men, for instance, sometimes seem unsettled by the thought of male pregnancy, but the reproductive reversal among the fish is often seen as kinda cute ("How sweet. A fishy dad taking care of his kids!"). As shown by a study by Kimberly Paczolt and Adam Jones published this week in Nature, however, there can be a…