10. Parthenogenetic lizards
Perhaps it is precisely because reproduction is so magical that the stories of "virgin birth" emerge one after another and spread to this day. One of the most famous is the birth of Jesus. It is said that his mother, the Virgin Mary, was a virgin when she was pregnant.
Although virginity is technically feasible, it's hard to believe that. However, in nature, parthenogenesis (scientific name of virgin birth) is very common. Hammerhead sharks, Komodo dragons, moles salamanders and other kinds of reptiles, fish and insects can reproduce directly without mating.
It all starts with the germ cell. This kind of cell can be divided into two, then two into four. We call these four germ cells' gametes'. Three of them will be discarded, and the remaining one will contain half of the chromosomes needed to create new life. In sexual reproduction, a female gamete combines with a male gamete to form a complete set of chromosomes.
But in parthenogenesis, a female gamete, or an egg, contains the chromosomes needed by the whole organism, stimulates its own growth, and eventually becomes a new individual.
It's incredible that many insects can easily swim between parthenogenesis and sexual reproduction, and the choice of breeding mode depends entirely on the environment (for example, whether heterosexual mating can be found). In addition, some organisms follow the so-called 'periodic parthenogenesis'. For example, Daphnia alternates parthenogenesis and sexual reproduction.
So far, no mammalian parthenogenesis has been found in nature. However, the Parthenogenesis of rabbits and other small animals has been successfully induced by temperature control and chemical control. But human beings have no reason for this.
9. Male and female Nemo
Don't confuse hermaphroditism with parthenogenesis! These are two completely different concepts. Parthenogenesis means that the female gamete can complete all the reproductive work alone. The secret of hermaphroditism is that the organism has both male and female reproductive organs, and can produce both female and male gametes.
Hermaphroditism is common in some species, such as flowers, snails and fish. Some of them are born male, but can become female in the future; others are born female, but can become male the day after tomorrow. Some species are androgynous throughout their lives.
Remember finding nemo ）Nemo and his father in the movie? It's necessary to make a sequel to the movie. You don't know how interesting the reproduction of clownfish is! Generally speaking, clownfish like to shuttle between sea anemones in groups. Except for the leading pair of adult male and female clownfish, the rest are infertile young males.
But for example, if the leader's female dies, the leader's male will become the leader's female. At the same time, the strongest one in the group of young males will grow and mature rapidly, and become the leader's male to bear the responsibility of fertility. Pixar! Come on! We can't wait to see the sequel. Rinmo's father suddenly becomes a mother. That must be a big selling point!
8. Male frogs stealing eggs
Stealing eggs is a kind of reproductive strategy, but at first glance, it seems that frogs are covered with sports goggles, drinking rum, holding bayonets to steal eggs.
This is not the case. It's really about frogs, but they're naked frogs that live in the Pyrenees, not Barbados. The fact that they are "naked" is very important because the long night is so cold in the high Pyrenees that these frogs, who like to make humans under the cover of night, have to arrange it in a sunny afternoon.
Thanks to the unique geographical conditions here, the researchers were able to closely observe the fertilization process of this frog, and found that this is not the same as their usual in vitro fertilization method.
In vitro fertilization is the first choice for fish and amphibians. The female lays a nest of eggs in the water, and then the male lays sperm on the eggs. The frogs want to make sure that the process is not delayed, so when the female is ready to lay eggs, the male climbs onto her back and gives her a big bear hug. After the female lays her eggs, the male fertilizes her immediately. However, the fertilization rate may be only about 1%.
In the pond on the high Pyrenees, the romance of frogs is different. The number of male frogs is far more than that of female frogs, so they often can't find a mate, which forces the male frog pirates to look for new eggs everywhere. Once they find the pile, they will try their best to fertilize the unfertilized eggs. Researchers have found that a fertilized egg in an egg pile has four fathers!
7. Honeybee orchid to attract bees
Most flowers and the pollinators that help them reproduce are in a mutually supportive relationship. For example, bees, butterflies, hummingbirds and other animals will pollinate flowers while sucking a mouthful of sweet nectar in return. After that, the pollinated flowers can gradually bear seeds, which can eventually grow into new plants.
Although this method of reproduction is not boring, some varieties of orchids dislike it as too old-fashioned. Pollinators keep busy among the nearby flowers, but orchids worry about inbreeding. Although we know they don't really worry about it, biological evolution has given birth to more novel (actually super weird) ways of self reproduction to meet the needs of these creatures.
In the mountains along the Mediterranean, there is a kind of plant called Ophrys apifera, and people prefer to call it honeybee flower. Under the effect of the visual trap, the flower really looks like a female bee with her head buried in the blue petals and only her back out. In addition, the bee orchid can also release the smell similar to that of the female bee, and even has villus, which makes it look hairy and deepens this sensory illusion. This kind of deception is so perfect that it turns its appearance defects into advantages.
Attracted by the magic of the bee orchid, the drones scramble to mate with the flowers, and the pollen with special stickiness in advance will stick to the drone's back. But according to the original plan, deception can only last so long. Xiongfeng in order to meet the sexual desire of the bee orchid after the implementation of the brutal destruction, only to realize that he was deceived, so with the loss, staggering away. Drones will fly a long distance to 'heal' until they fall into the trap next time. If everything goes well, the pollen loaded by the drone will unconsciously fall on another flower.
In the case of Cymbidium, the loss of the male peak is just in the eye, because the farther the male bee flies in the calm process, the more it can prevent the inbreeding of Cymbidium. Of course, think about all kinds of orchids on the windowsill. There are so many kinds of orchids in the world. Bees are not the only animals attracted by their magic.
6. Tetrahymena of seven sexes
The next time you cool off by the lake, try to forget the fact that hairy, single celled microbes are doing some very strange breeding around you. In fact, Tetrahymena is a very pure creature in most cases. It uses chaste parthenogenesis to produce its offspring in the fresh water where it lives.
But parthenogenesis can not produce genetic variation, and genetic variation can help organisms adapt to environmental changes. Therefore, when the surrounding environment becomes unsuitable for survival, Tetrahymena will activate the dormant sexual desire to help itself survive. At that time, things became very interesting.
If you think the study of gender politics is very complicated, think about it. This tiny microorganism has no less than seven genders! Imaginative scientists call these seven genders type 1 to type 7. Tetrahymena with both sexes of type 1 cannot mate, but don't worry, it can mate with any of the other six sexes.
The newly formed Tetrahymena carry all the genes of their parents, so they can also transform into any of the seven genders. Then, after random selection, their DNA set will be pruned and eventually only one sex will be retained. It's a pretty complicated thing for a tiny microbe.
5. Hippocampus of male reproduction
Many people have forgotten the plot of the movie 'Junior', starring Schwarzenegger and DeVito. For the sake of popular science, this article is to remind you that this movie is about the pregnancy of the future governor of California. Male pregnancy? It's fun. The next content is more interesting.
Male pregnancy is obviously a big brain hole idea, but if the comedy to seahorse to see, they most useless shrug. It's not that the movie has a 32% rating on rotten tomatoes, but that in the hippocampus, it's really no surprise that a male is pregnant.
When the seahorses want to reproduce, the male and female seahorses will dance a delicate, long and wonderful courtship dance together. Their tails are intertwined and they swim in pairs. When their dance steps are fully synchronized, the female hippocampus will slide 2000 eggs into the male hippocampus's special pouch for pregnancy.
The male hippocampus fertilizes these eggs and keeps the fertilized eggs in the pouch in which they are hatched. He will take good care of these fertilized eggs and try his best to meet their needs at different stages of growth. When the young seahorses are ready to face the world alone, the male seahorses contract the muscles of the pouch and 'produce' them.
Meanwhile, the female hippocampus has been preparing for the next ovulation. It's Tango time again! The male seahorse can have a baby in the morning and get pregnant again in the evening.
4. Barnacles in the magpie's nest
Now let's look at the terrible way parasites reproduce. When it comes to parasites, the way they reproduce is often bizarre, creepy and impressive. It's really not easy to pick out the more distinctive ones. However, the barnacle (rhizocephalans), a kind of humble root head crustacean, is worth our attention because of its unscrupulous reproduction.
Rhizocephalans, or rhozo for short, are different from our common barnacles in appearance. Their larvae are floating on the sea, waiting for a chance to meet passing crabs. The sea is vast and the opportunity is slim, but there are so many barnacles that some larvae can find their target.
Once the barnacle finds a group of crabs, it will immediately adhere to the crab, extend the tentacle like a syringe, and inject its cells into the crab. The barnacle cells gather in the crab's sinuses, then begin to take root and grow, spread everywhere, and finally stick out their heads in the female's ovaries and lay eggs in the crab's small abdomen.