Female shark gives birth despite not seeing a male for 4 years

A female shark at the Brookfield Zoo in Illinois gave birth to a baby shark despite not having contact with a male shark for the past four years.

The young epaulette shark appears healthy and eating well. Photo: Brookfield Zoo — The young epaulette shark appears healthy and eating well. Photo: *Brookfield Zoo*

The birth, which took place on August 23 after a five-month gestation period, is the second recorded birth without fertilization in a captive epaulette shark ( Hemiscyllium ocellatum ), Live Science reported on November 9. Animal caretakers kept the baby shark in isolation for two months to monitor it. The 13- to 15-cm-long calf will now be on display in the zoo's "Living Coasts" area.

Parthenogenesis is a form of asexual reproduction in species that normally reproduce sexually. It has been observed in captive birds, sharks, lizards, and snakes. In June 2023, scientists witnessed the first parthenogenesis of alligators. Females of species capable of parthenogenesis lay eggs containing all the necessary genetic information. Mammals cannot reproduce asexually because they require genes from sperm.

The mother shark arrived at Brookfield Zoo in 2019 from the New England Aquarium. Since then, she has not lived with a male. She reached sexual maturity last year at age 7 and began laying two to four eggs a month. One of those eggs developed into an embryo without being fertilized by the male’s genetic material.

According to Mike Masellis, animal care specialist at Brookfield Zoo, baby sharks born via parthenogenesis can be very fragile. However, the newborn epaulette shark appears to be quite healthy, eating finely chopped fish roe, minced squid tentacles and other finer foods.

Epaulette sharks are mostly nocturnal and can grow to 1.1 meters in length, according to the Australian Museum. They live in the Great Barrier Reef off Queensland, Australia, from the northern tip of Cape York Peninsula to the Capricorn Islands and Bunker Group. The elongated sharks are named for the large eye spots above their pectoral fins, which make them appear larger. Epaulette sharks can walk short distances on sandy seabeds, using their powerful pectoral fins to move.

An Khang (According to Live Science )

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