Groundbreaking research reveals sharks can taste bitterness just like humans

This groundbreaking discovery was made by scientists from universities in Cologne and Freising, and it provides a new perspective on the evolution of taste. They found through genetic research that sharks, like humans, are also able to perceive bitter tastes. The results of the research were shared in the prestigious weekly scientific journal "PNAS".

In fact, the researchers proved through their genetic studies that sharks, which are among the oldest species on Earth, have had receptors for bitterness from the very beginning. Interestingly, humans also possess these receptors, despite our last common ancestor with sharks existing about 500 million years ago. It is a team of German researchers conducting studies at universities in Cologne and Freising who made this fascinating discovery.

The scientists identified bitter taste receptors in twelve cartilaginous fish species, which includes sharks and rays. These receptors were found to belong to the so-called 'type 2', something also present in us humans. These receptors enable the identification of bitter and potentially toxic foods. Until this study, it was thought that this type of receptor was found only in bony vertebrates.

Dr. Sigrun Korsching from the University of Cologne highlights the significance of these findings. She mentions, "The latest research allows us a glimpse back 500 million years to the molecular and functional beginnings of the entire family of bitter taste receptors".

So far, the analysis of shark genomes has been quite challenging due to their considerable sizes. Sequencing these genomes is far more complicated and time-consuming than for a majority of other animal species. However, due to advancements in sequencing techniques, scientists are now increasingly able to explore the genes of cartilaginous fish.

During their research, the scientists studied 94 bitter substances that humans can recognize. They found that sharks' receptors could also identify 11 of these substances. Interestingly, some of these substances also trigger the bitter taste receptors in what's known as the 'living fossil' – the coelacanth.