Bioluminescence is a biological feature of some animals to produce their own light source. They may do so for a variety of reasons, including but not limited to: luring in prey, scaring off predators, camouflaging with their surroundings, and communicating with others.
Image Credit: The Kid Should See This
Bioluminescence is all around us; not only can a wide variety of sea animals seem to take advantage of the ability, but there are even some land animals that are capable of it as well. On the other hand, deep sea creatures, including certain types of fish, seem to be the most common of the bunch to have the ability.
But how common is bioluminescence in our oceans? A genetic-based study published in PLOS One points to the fact that bioluminescence has evolved independently up to 27 different times, which suggests that the biological feature is one that seems to be necessary for the survival of many types of fish in the ocean.
"When things evolve independently multiples times, we can infer that the feature is useful," said W. Leo Smith, a co-author of the study from the University of Kansas.
"You have this whole habitat where everything that's not living at the top or bottom of the ocean or along the edges—nearly every vertebrate living in the open water—around 80 percent of those fish species are bioluminescent. So this tells us bioluminescence is almost a requirement for fishes to be successful."
The bioluminescent abilities are said to have developed around 150 million years ago. After the pioneering species developed the ability, they passed it on to new species as evolution took place.
One example of an evolved fish capable of bioluminescence is the bristlemouth: "The bristlemouth is the most abundant vertebrate on Earth," Smith said. "Estimates of the size are thousands of trillions of bristlemouth fish in the world's oceans."
With so many specimens of fish apparently having the genetics necessary to be capable of bioluminescence in this day in age, the study implies that our oceans are filled with a whole lot more bioluminescent fish than we originally thought.
In fact, in many scenarios under the ocean’s surface, light is much more scarce, and animals actually have to produce their own light in order to survive. Whether it means drawing in their prey to go in for the kill, or being able to signal to other creatures when the naked eye alone isn’t enough, bioluminescence seems to be their answer to all these problems.
Smith and the other co-authors in the study are reportedly now in the works of trying to determine exactly what gene it is that makes bioluminescence possible. They will be working on trying to distinguish differences between bioluminescent genes and normal genes to see where they differ; these patterns may help use better understand its origins and variants in different species.
Source: The University of Kansas via Phys.org
