Horns are one of the accessories commonly found in ruminant mammals, especially male animals. Males have various forms of horns to attract females during the mating season and are used to duel other males when fighting over mates. However, it turns out that the existence of this horn has its secrets. A recent study by a joint research team from China and Denmark revealed the secrets behind horn development, which have implications for the development of human cells. Initially, researchers were interested in studying the evolutionary origins of horns in ruminants, which have a variety of structures and shapes. Aside from that, if you don’t have any experience in hunting a deer in the mating season, we recommend you find where to hunt during the rut.
For example, deer and roe have antlers called antlers, which are composed of a skeleton covered with skin and special nerve tissue that can grow and change every year. Another case with giraffes, which have ossicle horns, which are composed of bones covered in skin and fine hair. Meanwhile, cows and sheep have horns covered with a layer of dry, hardened keratin, leaving little hollow space inside.
Although they have various structures and shapes, it turns out that these various horns are formed by the same genes. Based on analyzes conducted on the genomes of 44 different ruminant species, including cattle, deer, antelope, giraffe, sheep, etc., it was revealed that they were all regulated by the same gene group. This suggests that the evolution of the horns occurred only once, that is, in the common ancestor of modern ruminants that exist today. The gene responsible for the formation of the horn is thought to regulate the embryonic tissue known as the neural crest. Comparison and genetic analysis of two hornless ruminants, the musk deer and water deer species, confirm this because they have mutations in these genes so they cannot have horns.
Another thing that was revealed was, the eight active genes involved in the formation of horns in these animals are genes that also play a role in tumor formation and growth. In contrast to uncontrolled bone cancer (osteosarcoma), horn growth is regulated through activation and inactivation of different cancer genes. That is, the horn is an organ structure produced by the controlled growth of bone cancer cells.