Parasite, the word is linked to murderous greed in our hearts. The great cuckoo, commonly known as the cuckoo, is a typical parasite, but for the entire population living in the northern hemisphere, it is pleasant to hear the first call of the cuckoo in spring.
Big cuckoo, cuckoo
Messenger of Spring
Close your eyes and reminisce about spring: the world of Xiao Cha is re-dyed with color, the earth awakens, and the buds bloom. A large gray bird appeared, seemingly out of nowhere. From a distance, it looks a lot like a top-of-the-food chain predator, the Sparrowhawk (Sparrowhawk), but a cry reveals its true identity: cuckoo.
Imitate sparrowhawks
For thousands of years, this onomatopoeia-named bird has been a harbinger of spring, a darling of the poet's brilliant pen, immortal in art, literature and language.
Oh, no, Li Bai and Du Fu respectively wrote "Sunrise Cuckoo Ming, Tian Family Embraces Hoe Plow." "The Tian family hopes that the rain will dry up, and the cuckoo will urge spring planting everywhere." Such a charming sentence.
The cries of "cuckoo cuckoos", in fact, are produced only by male cuckoos: they usually make sounds at intervals of 1-1.5 seconds, 10-20 times per group, with a few seconds of rest between each group. When approaching a potential female mater, the male also dances a swing dance — swinging his tail from side to side, or body.
By June, when the breeding season is over, the male cuckoos have basically "forgotten their tune."
Where the cuckoo goes
But it's not just the call that appeals, the cuckoo's behavior has always intrigued scientists. Where did they go after summer?
It may have taken us thousands of years to figure out where these birds went — in some ways, the truth is more bizarre than imaginary imagination.
Eurasian cuckoos are among the best long-distance migrants in the world: they spend part of the year with us (arriving in Eurasia in March and April, starting to fly in August and September), living the rest of the year in tropical Africa, such as the Congo Basin, and actually spending most of the year living with elephants and chimpanzees in the African rainforest!
Take the cuckoos living in Beijing, for example: In 2016, researchers recorded through tracking devices that they took off from Beijing, passed through Yunnan, crossed the Indian Ocean, and finally reached Mozambique in southern Africa. The journey spanned 16 countries and covered more than 50,000 kilometers.
Free cuckoo
Cuckoos can leave freely, but also because of their infamous breeding behavior: eggs lay in the host nest, and adult cuckoos are free to return to warmer climates when foster parents are busy feeding the chicks.
Once the cuckoo has found a suitable nest, she will wait quietly until the nest owner lays the first egg. Then, she'll find the right opportunity — usually to lay her own eggs later in the day.
How to find opportunities? Show your face and make a sound.
A 2011 paper published in Behavioral Ecology, "Parasites in Wolf's Skin: Cuckoo Imitations of Eagles," noted that adult cuckoos resemble sparrowhawks, and that female cuckoos never call "cuckoos" but instead make a shrill call similar to that of the bird of prey sparrowhawks, which helps cuckoos approach the nests of potential hosts.
Most birds, when they see or hear sparrow eagles or cuckoos, show the same panic and escape; Although the brave reed warbler will beckon its neighbors to attack the cuckoo/sparrowhawk swarm, leaving the nest also gives the cuckoo the opportunity to steal the egg.
The eggs lay very fast. How fast is it? Sometimes, before an inexperienced cuckoo can fly into the parasitic object's nest, the egg comes out and lands on the ground.
No big deal, a cuckoo can produce up to 25 eggs, and practice can make perfect.
Parasitize with righteousness
Cuckoos hatch faster than the average bird, and evolution has given them a large orange beak that attracts host parents to work around the clock to feed them.
This is not to say that parasitic parents happily accept fate, there has been an arms race between cuckoos and hosts.
A new study from 2020 showed that 66% of reed warblers among the most parasitic species accepted these fat children from unknown origins; 12% of reed warblers throw it out of the nest; 20% of the reed warblers can't be fed, and simply abandon the nest...
Evolution is really adaptation. For different parasitic environments, the cuckoo of the jī zéi exhibits very different behaviors.
In the face of small adoptive parents, cuckoo chicks usually expel the remaining eggs from their nests in order to feed themselves; But there are exceptions – when the adoptive parents are magpies and crows, the adopted son of the cuckoo is a good child.
He is very well-behaved when he lives with magpies and crows
Crows and magpies, usually gregarious, are involved in caring for and feeding young birds. Parasitic in such a wealthy family, the little cuckoo does not worry about eating and drinking, not only is it not aggressive, but also secretes a black stinky liquid to defend the nest.
clever
Write at the end
As a bird that feeds mainly on insects, the moth-like caterpillars that generally do not have a mouth and are full of spikes are the staple food of cuckoos, so their significance to the environment is extraordinary.
As for parasitism? Any "moral kidnapping" of cuckoo behavior is not smart enough, they are like all sentient beings, looking for their own way in reproduction.
The author thanks you for your attention (- _-)