Animals that have lived for 450 million years are being pumped by humans in a blood frenzy that kills 110,000 per year

Long before the birth of man, the earth has been the home of many animals. But with the emergence of humans and the expansion of their activities all over the world, the living space of many animals has been drastically compressed, and some are even headed for extinction. A big reason some animals are facing extinction is the endless demands of humans, such as the horseshoe crabs that this article will talk about, which are heavily pumped by humans because of their unique blue blood.

Horseshoe crabs are also known as horseshoe crabs, and they are marine arthropods. They normally live in shallow areas and feed on a variety of small marine animals. During the breeding season, male and female horseshoe crabs come to the beach in pairs, like mandarin ducks, to lay their eggs.

Horseshoe crabs are one of the oldest animals on Earth today, with fossil evidence showing that they appeared at least 450 million years ago in the Ordovician period. This was during the great Ordovician biological radiation when marine biodiversity increased dramatically, but there were no animals on Earth's land yet, and dinosaurs would not appear for another 200 million years.

Horseshoe crabs have experienced five of the most severe species extinction events on Earth, including the Permian-Triassic extinction event, which led to the extinction of 96% of marine life, and the Cretaceous-Paleocene extinction event, which led to the disappearance of non-avian dinosaurs. Species that lived in the same period as the horseshoe crab originally became nearly extinct, and species that appeared later than the horseshoe crab have mostly become extinct.

Judging from fossils, the present-day horseshoe crab has changed little from its ancestor's hundreds of millions of years ago. Because of this, horseshoe crabs are called living fossils. Currently, there are only four species of horseshoe crabs left in the world, namely the Chinese horseshoe crab, the round-tailed horseshoe crab, the southern horseshoe crab, and the American horseshoe crab, which are found along the coast of China.

The oxygen-binding protein in most animals contains iron atoms, so the blood appears red. However, the blood of horseshoe crabs is unique in that it is blue, and they contain hemocyanin in its blood. This protein contains copper atoms, which become copper ions when they are oxidized and take on a blue color.

In the 1950s, scientists extracted horseshoe crab amoeboid lysate (LAL) from the blood of horseshoe crabs, and this horseshoe crab reagent quickly coagulates when combined with bacterial endotoxin, so the horseshoe crab reagent is a very efficient toxin detection reagent, and human demand for horseshoe crab blood is very high.

Thus, humans began a frenzy of horseshoe crab fishing and blood draws, with most of each horseshoe crab having 30 to 40 percent of its blood drawn from its body. Although the horseshoe crabs are then released after being bled, some horseshoe crabs die after too much blood is drawn, and they may also die during transportation.

According to statistics, as many as 750,000 horseshoe crabs are currently captured for blood draws each year. The mortality rate of horseshoe crabs after being blood drawn is estimated to be 15%, with the high possibility of going up to 30%. That means that at least 110,000 horseshoe crabs die each year because of human blood draws.

Globally, the United States has the highest demand for horseshoe crabs, with an average of 525,000 American horseshoe crabs caught in the country each year between 2013 and 2017. In addition, as many as 1 million American horseshoe crabs are used each year as bait for eel and eel snail fishing. In Delaware Bay, where American horseshoe crabs are most abundant, the population has declined from 1.24 million in 1990 to less than 334,000 in 2002.

The population of American horseshoe crabs is declining significantly due to overfishing, which also threatens the red-bellied shorebird, which feeds on the eggs of American horseshoe crabs. During the breeding season, a single female horseshoe crab can lay as many as 80,000 eggs. In recent decades, the population of red-bellied shorebirds has declined by 80 percent and they have become a near-threatened species, not unrelated to the dramatic decline in horseshoe crab populations.

Not only are horseshoe crabs susceptible to death after being blooded, but they also further reduce their offspring. The mobility of horseshoe crabs is necessary for reproduction and egg production, but when they are blooded, their mobility is reduced, which is very detrimental to the population size of the horseshoe crab.

Especially with the high number of vaccines produced in the past two years, more horseshoe crab reagents are needed by researchers to test vaccines for contamination with toxins. As human demand for horseshoe crabs has grown, the price of horseshoe crab blood has risen, with each liter of horseshoe crab blood worth up to $100,000.

As horseshoe crab populations have declined dramatically, they have been classified as protected animals around the world. But humans still have to perform a lot of botulinum toxin testing, and to protect the dwindling number of horseshoe crabs, other alternatives have to be sought.

Scientists have extracted an enzyme, horseshoe crab clotting factor (RFC), from the blood of horseshoe crabs, and they can be tested in the same way as extracted horseshoe crab blood, and most critically, they can be produced by recombination. If this technology can be developed and promoted, it can effectively reduce the human demand for horseshoe crab blood.

Horseshoe crabs have been living on earth since long before the emergence of humans, and the endless demand of humans has undoubtedly posed a great threat to the survival of horseshoe crabs. Don't let the greed of humans turn this ancient species of horseshoe crab into a fossil!