: Popular Science China
Production: Su Chengyu
Producer: Chinese Academy of Sciences Computer Network Information Center
Speaking of the male seahorse, most of the impression of it is a model "good dad" in the animal world.
Because when the hippocampus mate, the female hippocampus will lay eggs in the male hippocampus' nursery bag. The male hippocampus is responsible for the combination of sperm and egg, and then conceive, wait for 10-25 days to give birth. The baby pouch of the hippocampus can be understood as the structure of the mammalian uterus, which provides nutrients and oxygen to the embryo.
△The pregnant seahorse dad has a big belly. Source: the conversation
The mother is responsible for the birth of other animals, while the father is responsible for the seahorse. The title of "good daddy" for male seahorses came from this.
△The seahorse father will produce hundreds of small seahorses
at a time. Source: scroll.in
Not only give birth to children, but at the beginning of courtship, the seahorse is also different from other mainstream animals. The seahorse is a woman chasing a man, not a man chasing a woman. The female seahorse will use gorgeous decorations or elaborate dances to dance with the male. After all, the tiring work of giving birth to a child is entrusted to Dad, and it seems that it is right to show good wishes to Dad Haima. When talking about seahorses,
generally refers to the genus Hippocampus. The genus Hippocampus belongs to the subfamily Hippocampus. The reproductive characteristics of are the same throughout the Hippocampus family. The males are responsible for giving birth. Z2z is the same. .
△Ghost Sea Dragon
Source: Brook Peterson/Stocktrek Images, via Science Source
As everyone knows, the image of a good man and a good father like the seahorse will also be subverted one day.
According to a 2018 study published in "Reports of the Royal Society", good seahorse fathers sometimes may not be reliable, they also have scum. So what exactly is the scum?
Good dad will selectively abortion
In the study, scientists raised a number of sea dragons, both male and female. In 5 days, males can mate freely with females, and after mating, the males and females are separated.
△Short-kissed sea dragon, source: Roberto Pillon
Sea dragon's prospective father was divided into 3 groups, one group and one water tank.
In the first group of water tanks, there are strange females of the same size staying with the prospective father.
In the second set of water tanks, with the father-to-be, there are strange females much larger than her. It is worth noting that in the sea dragon world, the bigger the body, the more sexy.
In the third group of water tanks, the original spouse stayed with the prospective father, and the father and mother were together.
The short-nose sea dragon
bred in the water tank in the experiment. Source: observador
It was found that the sea dragon father-to-be in the second group of water tanks could not stand the temptation and became scum. Those expectant dads who come into contact with unfamiliar and sexier females have a short period of pregnancy, lack of nutrients in their embryos, and insufficient development time. The baby sea dragons born are very weak and small, and some of them are deformed. This is not bad, some fathers-to-be even if they are half pregnant, they will choose to abort.
Scientists believe that Sea Dragon’s father chose to be a scum man to reduce the nutrient output of pregnancy and even stop pregnancy, so that can reserve more energy and energy to mate with more attractive new heterosexuals and produce better offspring. The
researchers gave this phenomenon of "Dad Hailong’s abortion due to the appearance of the sexy opposite sex" a literary name: the phenomenon of women in red (Women in Red effect). This is the name of a movie made by Gene Wilder in 1984. The movie tells a married man's fascination with a sexy red girl. This fascination eventually split his family apart.
△Lady in Red Movie Poster
Source: Wikipedia
Where did the aborted embryo go? The aborted embryos of
were not abandoned outside the body, but were transformed into his own by Sea Dragon’s father.Divided, re-absorbed, no waste at all.
A long time ago, scientists discovered that sometimes when Hailong's father became pregnant, the number of embryos decreased strangely, but they did not know where the reduced embryonic nutrients went. In 2009, scientists conducted experiments on this problem with the bottlenose sea dragon. Before the female sea dragons mate, the scientists used carbon 14 amino acids to mark the female eggs in order to track the whereabouts of the eggs. After the male of
mated and became pregnant, it was found that these carbon 14-labeled amino acids were transferred to the male's nursery bag, liver and muscle tissue .
△Part of the nutrients flowed into the father-to-be’s liver and muscles.
Source: Literature 2
Those in the nursery bag are better explained, that is a normal developing embryo, which is about to be born, and markers are normal. And those embryos that ran into the liver and muscles meant that the disappeared embryos became the nutrients for the sea dragon father, and eventually became part of its body.
This also illustrates another problem. For the sea dragon father, not every embryo is important to . If is necessary, such as when the nutrients are insufficient, it will recover the nutrients given to the embryo and convert it into its own energy again. For another example, if you encounter a sexier opposite sex, you will also reabsorb embryos so that you can reassign them to future embryos after you get pregnant again. The phenomenon that
causes pregnancy interruption due to some factors is also called Bruce Effect (Bruce Effect). This was once considered an evolutionary strategy for females to fight male infanticide. Because H.M. Bruce (1959) was first discovered by a man named Bruce. He discovered it while doing experiments on mice, so he took this name.
He found that shortly after mating female mice, direct contact with unfamiliar male mice or exposure to the environment containing the chemical smell of unfamiliar male mice will increase the possibility of female mice miscarriage, while contact with male mice and their scents This phenomenon will not occur. The phenomenon of
is also found in other mammals. For example, prairie vole, lemming, lion, horse, baboon, etc. Now he joined a new member of the sea, Hailong.
After reading this article, do you still think that hippocampus (again, hippocampus belongs to the sea dragon family, they use the same reproductive strategy) is a good father?
References:
1, https://royalsocietypublishing.org/doi/full/10.1098/rspb.2018.1335
2, https://royalsocietypublishing.org/doi/abs/10.1098/rspb.2009.1767
3, https://xuewen. cnki.net/R2006060800000464.html
