Whale Shark Life Explained as a Nuclear Test By-product

The whale shark is the world’s largest fish, reaching 18m in length, and is classified as an endangered species. In other studies so far, whale sharks have been estimated to live for about 130 years, but in nuclear tests, radiocarbons artificially released into the atmosphere appear in the spine of whale sharks. It is said that the life span has been explained.

A research team at Rutgers University in the United States revealed that it was possible to investigate the absolute age of various fish using radiocarbon dating, but this time it was applied to the spine of a whale shark. The research team obtained samples of whale shark spine bones. Samples from whale shark carcasses obtained in Taiwan in 2005 and Pakistan in 2012. First, the spine is photographed under a microscope and the bone cross section is calculated as if counting tree rings. Of course, it is not possible to estimate the age of the whale shark alone, as it is not known how fast these bone sections will grow.

Accordingly, radiocarbon information was used. The concentration of carbon 14 in the atmosphere fluctuated significantly as the US and Soviet countries left nuclear bombs in the atmosphere from the 1950s to the 1960s. This carbon can be deposited in the food chain and appear in animal tissues. The research team used this as a time stamp.

As a result of measuring radiocarbon dating by accelerator mass spectrometry AMS, it was found that one of the three species of whale sharks in Taiwan was formed in 1972. In the case of the whale shark in Pakistan, carbon analysis is increasing every year, so the team was able to estimate the age of the whale shark to be 50 years old. Some whale sharks weren’t dead because of their longevity, they could live longer, but this method confirmed the whale shark’s last age.

The research results were published in the journal Frontiers in marine Science. Radiocarbon dating methods are already used in various fields such as conservation of nature, biology, and forensic medicine, but can be an important tool for the study of endangered species such as whale sharks.

One expert said that knowing the age and size of a fish can calculate the growth rate. This is an important variable in investigation and management, and shows how fertile and at what rate the species can recover if the species population decreases due to overfishing, etc. It is because of it. In the case of whale sharks, it is quite slow to grow to a large size, and maturity is around 30 years old. Related information can be found here .