There is a multitude of words one can use in an attempt to describe an elephant: behemoth, complex, wise and majestic, just to mention a few. My favourite quote about these animals comes from South African botanist and zoologist, Lyall Watson:
“If elephants didn’t exist, you couldn’t invent one. They belong to a small group of living things so unlikely they challenge credulity and common sense.”
What he says couldn’t fit these animals more. Their colossal size, cascading trunks, butterfly-like ears, and spearing tusks make them one of the most unique and stand-out animals in the world. Today’s blog dives a little deeper into one of their most defining features – their tusks.
Elephants’ tusks are teeth that extend beyond their mouths. For most other animals, tusks are an example of elongated canines — the teeth that are used to rip apart meat. However, because elephants are herbivores and don’t have canine teeth, their tusks are created from elongated incisors — teeth that are used for crushing food.
As an elephant grows, so too does its tusk. Like our own teeth, the tusk is made up of dentine, a hard, dense, bony tissue and is wrapped in enamel. Enamel is one of the hardest animal tissues and can withstand a lot of wear and tear.
When coming across herds of elephants, you start to notice how different all the tusks are. Just like how humans have different teeth, so do elephants. Generally speaking, the tusks of male elephants grow at a faster rate than the females. This results in males having larger tusks than females and this is important in bull elephants’ dominance displays. The strongest and fittest bulls with larger tusks pass their genes to the next generation.
There are more modifications we see in elephant tusks that extend beyond male and female size differences. Just like most things, we must also consider the environmental and genetic influences that have an effect on the growth and differences of these tusks.
Out in nature, there are dynamics within the environment that affect change in certain animals and their anatomy. Here we see many elephants with one tusk longer than the other, or those that only bear one tusk. The reason for this has to do with the daily activities of elephants.
Elephants with one tusk larger than the other
The reason for this is quite simple: elephants show a preference for one tusk over the other. Many animals display this lateral dominance, just like left- or right-handedness in humans. In the case of elephants, it often results in one tusk that is strikingly different to its neighbour.
Elephants will favour a specific tusk to debark trees, dig up roots and lift objects. These actions cause the favoured tusk to be worn down.
Elephants with only one tusk
Just like us, elephants can also have problems with their teeth. While we might break a tooth by unexpectedly biting into something hard, elephants can chip a tusk or break it off in fights to enforce their right to mate. They can also crack and break their tusks while toppling giant trees to reach the nutritious new leaves that would otherwise be out of reach. Debarking Marula trees to reach the succulent cambium layer underneath the outer bark can also cause damage to their dominant tusk. Or damage to the tooth while very young preventing one from ever emerging.
If an elephant breaks its tusk, it will not grow back. Just like how if we lose a tooth as an adult it will not grow back.
There are individual traits of certain elephants that go beyond being affected by their daily actions, these individual traits are things that an elephant is born with and cannot change. When it comes to tusks, some elephant herds hold genes that contribute to individuals having very skew tusks, or even no tusks at all.
Elephants with skew tusks
When finding different herds of elephants around the reserve, it’s fun to notice that herds will often have individuals with specific tusk traits that differentiate them from other herds. Just like humans, genetics play a large role in the way an elephant’s tusk grows. For example, if both my mother and father have skew teeth, odds are my teeth will also grow to be skewed. If one of the parents of an elephant has skew tusks, that trait could be passed down to their offspring.
Because females will stay in their maternal herds and are all closely related, it is likely that they will share that trait of having skew tusks.
Elephants with no tusks at all
While many elephants use their tusks as valuable tools and weapons, not all elephants even have tusks. ‘Tusklessness’ is a natural genetic trait in female elephants with roughly 6% being born without tusks. This characteristic, however, is a little more complicated because it originally arose from environmental influences.
Before synthetic plastics and materials, ivory was the best material to use for a variety of things – elephant tusks can almost be considered the pre-20th-century plastic.
Historically, elephant tusks have been a sought-after material for humans. Today we make most tools out of plastic, but for thousands of years, ivory was among the best, if not the very best, option for buttons, hairpins, chopsticks, spear tips, bow tips, needles, combs, buckles, handles, and so on. For some of these items (piano keys being the most prominent example), we didn’t have a comparable alternative until very recently.
Unfortunately, because of the demand for ivory, which grew between 1979 and 1989, the ‘large tuskers’ were the first to be poached for their prominent tusks. This meant that elephants with the most prominent tusks were taken out of the breeding pool.
Elephants without tusks were not hunted, so they were able to mate and have their genes passed on to the next generation.
Fortunately, the ivory trade has been reduced in many parts of Africa and other materials are being utilised for everyday tools and instruments.
The uniqueness of elephants is so evident, and the individualisation of their tusks and how they use them is only one small aspect that makes these giants so interesting to watch. To go back to Watson’s quote, I really do think it would be almost impossible to try and recreate an elephant if it did not exist.
Robyn Morrison
Source link
