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  • It’s a dog eat dog worldbut just sometimes, if you want to get ahead out in the wild,

  • it pays to work together.

  • When different types of creatures interact with one another in the interest of survival,

  • it’s called a symbiosis, and intentional symbiotic relationships are surprisingly common

  • in nature.

  • Depending on who benefits from the relationship, partnerships can be either mutualistic, commensalistic,

  • or parasitic.

  • Mutualism is when both creatures benefit from being around each other.

  • Like at these remarkable underwater fish spas.

  • Upwelling, nutrient rich waters draw huge numbers and varieties of fish to seamounts

  • and reefs, but not all of them are here for the food.

  • Hammerhead sharks, turtles, and even manta rays make their way to these specific locations

  • for none other than a premium cleaning service.

  • These big fellas drift calmly around the reef, allowing smaller fish like wrasse, surgeonfish

  • and angelfish to pick off parasites and algae, leaving them feeling fresh.

  • The big fish get a luxury exfoliation, and the small fish get a tasty meal, so everyone’s

  • a winner!

  • Of course, there’s always that one friend that asks for just a little too much, and

  • in this case, it’s the manta ray, who times its visits to coincide with the sturgeon fish’s

  • spawning season, to get a free meal of fish eggs along with its wax and polish.

  • Which, frankly, just seems a little bit rude!

  • On the other hand, if only one creature in the partnership benefits, while the other

  • is relatively unaffected, it’s called commensalism.

  • Aphids are tiny insects that feed on plant sap. When they bite into a stem, the sugary

  • liquid surges out under high pressure, in through their mouths and straight out the

  • other end.

  • These back-end secretions are called honeydew, and they are a choice delicacy for their symbiotic

  • companions.

  • Because while the aphids are minding their own aphidy business, ANTS are actively farming

  • them, and creaming off the delicious honeydew.

  • Stroking their antennas over the aphidsbodies encourages a droplet of honeydew to

  • form, which they can then drink. The ants even move their aphid herds around to more

  • productive areas of the plant, when supplies start to dry up.

  • So, delicious drink for the ant, business as usual for the aphid.

  • Only, it’s not quite as innocuous as it seems.

  • In order to keep their aphidpetsat home, the ants resort to more aggressive tactics

  • that are definitely not business as usualripping off the aphidswings, and even

  • drugging them with chemicals from their feet, to make them stay in one place.

  • And since weve strayed into such sinister territory, let’s talk about parasitism,

  • the most toxic of symbiotic relationships.

  • In these partnerships, one creature benefits at the expense of another, and while the survival

  • of the parasite depends on the survival of the host, the freeloaders can often cause

  • illness and, eventually, death.

  • There are loads of parasites, from fleas to tapeworms, and even mistletoe. But by far

  • the creepiest out there is the Cordyceps fungus.

  • Cordyceps spores infect insects like this bullet ant, and in true zombie fashion, take

  • over its brain, making it climb high above the forest floor and clamp onto a twig with

  • its mouthparts.

  • Locked in this rictus grip, the fungus has the perfect anchor, and nutrients from the

  • insect’s body, to grow its fruiting body.

  • Once THIS matures, more spores will burst from its tip, and with the wide dispersal

  • that the high vantage point affords, can infect and decimate entire colonies.

  • And what’s even more terrifying is that there are thousands of varieties of Cordyceps

  • fungus, each capable of brainwashing a different insect before consuming it from the inside.

  • So, there you have it. Amazing symbiotic relationships that might not be so amazing for everyone

  • involved.

  • True, you can get ahead by working together, but as with so many things in life, it helps

  • to keep an eye out for yourself as well, or you could end up nothing more than a drugged

  • aphid.

  • If you enjoyed this video, be sure to give us a like, and if youre new around here,

  • click to subscribe and hit the bell icon to get our Earth Unplugged videos straight into

  • your inbox. Well see you next time!

It’s a dog eat dog worldbut just sometimes, if you want to get ahead out in the wild,

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極端な動物の関係 - アースアンプラグド (Extreme Animal Relationships - Earth Unplugged)

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    yulin に公開 2021 年 01 月 14 日
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