For many animals on the earth, the existence of natural predators is undoubtedly a terrible thing, so in the long road of evolution, animals have adopted a variety of survival strategies to avoid the trouble of natural predators. Animals such as elephants, for example, have evolved to be very large in size, which can be a powerful deterrent to potential predators, who will not attack them easily.
For example, animals like camels have evolved strong adaptability to harsh environments, so that they can safely live in areas that are difficult for predators to visit, while animals such as tigers and lions have evolved great strength to place themselves at the top of the food chain in nature, and of course have no natural predators.
Interestingly, in addition to these common strategies, some animals have adopted very strange strategies, such as the sea spider, which has been proven in 450 million years: as long as there is enough waste, there are no natural predators.
Sea spiders are arthropods that live in the ocean, and they are called sea spiders because they are similar in appearance to spiders, but they are not spiders, because from a taxonomic point of view, sea spiders belong to the "sea spider class", and spiders belong to the "arachnid class".
Fossil evidence suggests that sea spiders existed in the Earth's oceans as early as the Cambrian period about 450 million years ago, and that modern sea spiders have changed little compared to their ancient ancestors, and what sea spiders looked like 450 million years ago, what modern sea spiders looked like, and they basically did not evolve for such a long time.
However, in the oceans of the modern earth, sea spiders are very widely distributed, from tropical to cold, from shallow to deep sea, they can be found everywhere, which is enough to show that they are a successful species, and their survival strategy is very correct.
There are about 86 genera and more than 1,300 species of sea spiders on the earth, and their body sizes are large and small, the large ones can grow to tens of centimeters, while the small ones are only a few millimeters, although the body size of different species of sea spiders varies greatly, but their body structure is similar.
If you see sea spiders, it's hard not to notice their legs, because their legs are so conspicuous that the vast majority of their bodies are legs as a whole, and their heads and torsos are even negligible comparatively.
Sea spiders look very unpalatable, but the actual situation is indeed like this, their bodies are almost a "bone frame", which contains very little muscle and fat, for predators in the ocean, once they eat once, they will never have any interest in sea spiders again.
Yes, this is the survival strategy of sea spiders, and for those predators in the ocean, sea spiders are simply waste products without any nutritional value, so they have no natural predators in nature. So, how do sea spiders do it? The secret is in their legs.
According to the research of biologists, the legs of sea spiders are not only used to "walk", in fact, in their legs, they also contain their digestive system, circulatory system, respiratory system, etc., in the vernacular, those organs that originally grew in the stomachs of other animals to maintain life activities, but sea spiders almost all grow them into the legs.
In short, the intestines of sea spiders extend to the legs in the form of blind tubes, and while digesting, they can also use the peristalsis of the intestines to complete part of the functions of the circulatory system, and the overall shape of the sea spiders makes their body surface area relatively large, so they do not have lungs or gills, and only need to obtain oxygen in the water through the small holes on the surface of the legs.
This minimalist treatment makes the life activities of sea spiders do not need to consume too much energy, only a little food, they can survive, because they mainly feed on marine organisms such as cnidarians, polychaetes, sponges, bryozoans, etc., which can be said to be everywhere in the ocean, so they can be widely found in the earth's oceans.
It is worth mentioning that although the legs of the sea spiders seem to be well developed, they move much slower than expected, and they look like slow motion in a movie.
In fact, for sea spiders, there is no way to do it, after all, they only have a little muscle, but in the absence of natural predators, slow will not affect their survival. It is conceivable that if they want to be more agile, they will grow more muscles, but in doing so, they are likely to be coveted by predators.
As long as there is enough waste, there are no natural predators, sea spiders have proved in 450 million years that this strange survival strategy is actually feasible, I have to say, nature is really amazing, what do you think?