Discovering Walking Sharks
Sharks have populated the waters for hundreds of millions of years. During this long period, some species have barely changed, but extraordinary cases have recently been found, such as the walking shark.
Although we may think that there are no more animals to be discovered, the biodiversity of planet Earth never ceases to amaze us.
It is estimated that approximately 86% of terrestrial species and 91% of marine species remain to be identified. Of the latter, we do not know much data, as monitoring is very difficult.
That’s why it’s so surprising to find new species, such as the so-called walking sharks. Currently, nine species of these animals are known to inhabit the waters of New Guinea, northern Australia and eastern Indonesia.
All of these species belong to the genus Hemiscyllium, a family of tropical shallow-water sharks that live their entire lives among reefs.
Why are they known as walkers?
These animals support their fins to “walk” on the rocky bottom of tropical waters. When observed, it is clear that their movement resembles walking more than swimming.
Walking sharks move using the front pectoral fins along with the rear ventral fins. So they walk slowly and heavily across the seabed or even over coral reefs out of the water during low tide.
This mobility gives them an advantage over their prey at low tide and this allows them to become the main predator of the reef.
What are walking sharks like?
These sharks are small in size. They are nearly three feet long and have a thin, cylindrical body, with a ventral mouth and long tail. The species can be distinguished according to their pattern, which combines white painted and dark spots on the dorsal region.
The ability to move in this way and the ability to live in oxygen-poor environments make them good predators, although it is important to note that they are harmless to humans, so attacking these animals is totally unjustified.
The evolution of walking sharks
Sharks are animals that appear to have stopped in time, having changed little over the past 400 million years. For this reason, discovering this specialization is a unique achievement. The explanation may lie in the fact that they are isolated in tropical waters, where they live throughout their lives, without straying far from the place where they lay their eggs.
Walking shark species are believed to have evolved after sharks drifted away from their original population and genetically isolated themselves in other areas to, after millions of years of evolution, become new species.
Threats to walking sharks
This genus of sharks is in the vulnerable category according to the Red List of Endangered Species, but in fact their status is not exactly known as little is known about their biology.
Capture for use in aquariums and intensive fishing are the main threats faced by these animals. On the other hand, the effect of climate change and the destruction of its habitat are also factors that influence its conservation.
The destruction of their habitat can be very detrimental to them, as some species are limited to very small areas and are native to these places.
It is important to invest in the conservation of all the biodiversity we currently know (as well as the species we do not yet know) so that we can continue to appreciate and study animals in their natural habitat. Biodiversity enriches our planet.
