In the world of deer, the truth is widespread that males have horns and females do not, but deer are the exception that proves the rule. Both males and females grow horns, and in fact they keep them for different times. This is a trait that no other species in the deer family has. Cause is a kind of result of circumstance and biological luck, but it is a reflection of how complex the natural world can be.
Understanding the horns
Horns and horns are sometimes used synonymously, but there are some differences between the two that are worth noting. Horns are made of bone that is chemically identical to any other bone in the animal’s body, although they are protected by a sheath of keratin, the same protein that makes up our hair and nails on our hands and feet.
The main difference between horns and horns is that the former are seasonal while the latter are permanent. Horns are actually the fastest growing tissue on the planet, and they can expand at a rate of up to an inch per day. The main reason why antlers grow so quickly is a material known as velvet. This dense covering covers the growing horns from the outside and consists of dense blood vessels that supply the horns with nutrients and help protect against the risk of infection. The bone grows outward as an extension of the skull, so as not to hurt when the horns are shed.
Why antlers are grown on deer
Before we can discuss why female reindeer have unique antler growth, we need to understand what these unique physiological characteristics are and for what purpose they traditionally serve in the wild.
The main reason deer grow antlers – and one that makes the presence of antlers in female reindeer unfamiliar – is to fight for females and defend their territory during the rutting season. In fact, the growth and loss of antlers in most deer species coincide exactly with the rutting season. In reindeer, males begin to grow antlers in February and shed them in November or December. This leaves them hornless for two to three months and ensures that their antlers are at their largest and strongest during the rutting season – from about the end of September to the end of October or November.
The antlers do not necessarily grow back in the same shape every year, and larger antlers usually indicate older males. Each seasonal return of the horn is more glorious than the last.
How deer use antlers
Antlers seem to have evolved exclusively as a social mechanism, especially associated with the deer breeding cycle. Deer move in herds, but males are also very competitive in finding mates. During the mating season, male deer will test each other’s resolve in establishing territorial boundaries and will clash over who they will be allowed to breed with. Sometimes a pair of larger antlers is enough to scare off a potential groom, but deer often get into a fight.
Older male deer have large antlers, which usually allows you to control a large area and show interest in more females. As a result, older men tend to be more polygamous. At the end of the rutting season, young males usually leave the herd to join the bachelor herd until the mating season begins again. Elderly males may remain in their herd or may migrate elsewhere, but females usually remain with their sisters and mothers in the same herd for life.
How female cattle use their horns
The bull is a reference to a large number of roaming animals with horns, including many species, including goats, bulls, cattle and sheep. And while the horn differs in that it is a permanent structure rather than something that sheds annually, it is also a protective tool that males use to maintain breeding status. These herd animals have very similar habits to deer, and since the female bulls have horns, there is an intelligent connection that can be traced to the deer.
This is because while many male cattle have developed horns primarily as a way to compete for females, females seem to have developed it as a defense mechanism against predators. Horns tend to be more visible in larger species of females or in those living in high visibility conditions such as meadows. In other words, protective horns tend to develop in species that are less capable of hiding from predators. Moreover, this tends to be the case in species in which males travel in herds of bachelors, because this often results in herds of mostly females having to shelter their children from predators. The Caribou are in a similar situation.
Horny cycle of a female reindeer
Female reindeer have significantly less antlers than males. The male can grow horns up to 50 inches long after several seasons of molting, while the female is more likely to grow 20-inch horns. But these two can also be distinguished by the length of time they hold their horns. Females shed their antlers in May, just after the calves are born, but they begin to grow their antlers again later in the month. This leaves a very narrow period of time during which the female deer does not have antlers, and this ensures that their antlers are as full as possible during the vulnerable months of gestation.
Reindeer herds are very protective of their members – and especially their young – but this does not mean that there is no competition between females for resources. Since males rarely stay around to help raise their fawns, mother reindeer need to rely on their own wits to survive in the wild and ensure healthy pregnancies. For deer that live in ecosystems with abundant food, competition between females is not necessary. This does not apply to deer.
One strong hypothesis for why female caribou evolved to grow horns is the habitat in which they live – cold tundra with a noticeable lack of resources. The higher level of competition for food has led to the development of more aggressive traits in females. This seems to be reflected in the social structure of the reindeer herds. Here, females with larger horns enjoy a higher social status and have better access to food.
This is partly due to the functional role that antlers play. The impressive size of the reindeer antlers certainly makes them a good weapon for defense, but these antlers can also serve as an important tool for collecting debris in the wild. Horns are used to dig up potential food sources from frozen tundra and define territory. When the rut ends and the most devastating winter devastation sets in, caribou mothers are often left to their own devices without the care of men. And during the harshest months of the year, they use these impressive bone tools to carve out their food.
Next: elephant tusks: what are they made of and what are they for?