Featured Image Credit: Wikimedia
By Natalie Helbling
It has been known that many animals use their urine to mark their territory. From dogs, lemurs, wolves, lobsters, cats, and even bears, many species take advantage of their distinct urine smell to use as a warning sign! Creative and resourceful. Recent studies have shown that terrestrial animals are not the only ones to utilize their bladders. A species of Cichlids were used in a study that demonstrated fish also use their urine as a warning sign.
Welp… that’s one form of communication.
Two groups, one of small fish and one of large fish, were placed in a container with a glass divider. When the fish noticed the others’ presence, they suited up for battle. Fins came out and the fish charged the glass divider ready to fight. The smaller fish felt invincible and were not intimidated by the size difference of the larger fish. In addition to these physical changes, the fish released a different type of urine. Previously injected with a dye, the urine was easy to spot in the water. The glass divider prevented the fish from smelling each other’s urine, causing them to urinate more. When the experiment was repeated with a divider that contained a hole, the smaller fish quickly backed down once they came in contact with the larger fishes pee (gross).
This warning signal is hypothesized to be used amongst numerous fish species. More research will be conducted to fully understand the communication signal being released by these fish. There are many warning signs and signals in nature that can be unappealing to humans, but if it works to protect that species or individual, they need to keep on keeping on!