Mono Lake is one of the oldest lakes in North America and one of the harshest environments to survive.
Because the lake water has no outlet, the water continues to evaporate, leaving the salt in the lake, resulting in the salinity of the lake water being higher than that of the general seawater, extremely alkaline, and the PH value is as high as 10, which is higher than the seawater of PH8.
Despite the harsh conditions in Mono Lake, some creatures have survived.
The green algae in the lake grow and nourish a large number of shrimp in the harvest year, which undergo an annual cycle. In the cold of winter, the shrimp will disappear en masse, and in the spring, the shrimp will quietly multiply. In addition, there are sheets of black alkali flies flying on the surface of the lake.
The larval and adult pupae stages of the black alkali fly are spent in the lake and do not fly out of the water until adulthood.
In addition to this, it is almost impossible for most life forms to survive in Mono Lake.
In a lake with almost no life, a three-sex worm was discovered, and the California Institute of Technology found 8 incredible nematodes in and around the lake, one of which is a new and strange species.
The newly discovered nematode is named Auanema sp, which not only survives arsenic levels that are 500 times more tolerant in humans, but also has three sex forms.
In general, the sex of nematodes is divided into hermaphrodites and males, while new species have more females and, as males, also have unique genitalia.
The new species have even abandoned the typical way of spawning and reproduction, developing radical ways of directly giving birth to living organisms.
Nematodes are the most advantageous animals in Lake Mono
The researchers compared this strange new species of nematode to other nematodes of the same genus and found that other species of arsenic were also fairly well tolerated.
It is understandable that new species of organisms have evolved high tolerance in high arsenic environments, but strangely, other species do not live in environments with high arsenic content, why do they have such high arsenic tolerance?
The researchers gave the answer that the earliest nematodes were isolated from phosphate-rich soil and feces, and in the process of absorbing phosphate, arsenic was also absorbed, so the adaptation of nematodes to high concentrations of phosphate in the environment also increased the tolerance of arsenic.
In other words, nematodes have pre-adapted to life in extreme environments, and they have genetic resilience and flexibility, making it easier for them to live in harsh places like Mono Lake.
At last
Researchers believe that nematodes are definitely an "opportunist."
There are about 57 billion nematodes on Earth, and these creatures can survive in any extreme place on Earth.
In an extreme place, the evolution of an extreme creature is definitely not a coincidence, but the efforts and changes that organisms make in response to the pressure of survival.
We should recognize biological changes, and maybe when there are no other organisms, there will still be nematodes out there, who knows?