Are Elephants Evolving to Lose Their Tusks as a Response to Poaching?

Seeing evolution in action is rare and exciting, but unfortunately this example is simply depressing. Elephants are a perennial favorite of animal-lovers everywhere, with good reason. But their tusks, which evolved over millions of years because they aided the great beasts in their survival, now serve to put a target on their backs thanks to the human ivory market. The danger of poaching has become so significant and persistent that it constitutes a real selective pressure, which some elephant populations are responding to by producing new generations with shrinking tusks.

The general rule when it comes to natural selection is that traits that confer any measurable advantage, even a tiny 0.1% increase in survival, will spread throughout a species’ population. Over time, the trait may also become more pronounced over time, assuming this is possible and that in so doing the survival advantage also increases. It’s rarely quite that simple, though, as many traits come with a slew of both advantages and disadvantages.

For example, the power of flight is hugely effective as a defense mechanism for many birds. In the open, where any potential predators can be seen from far away, a duck or pigeon has little to fear from a hunting cat, when they can be airborne well before the predator closes the gap. But there are disadvantages even to wings. The highly-developed chest musculature needed to operate working wings has a high energy cost to build and to maintain. In environments where flight has proven less crucial, bird species like kiwis and turkeys have given up their wings and the power of flight.

This isn’t simply a case of “use it or lose it.” There is an active selective pressure against energy-expensive traits like wings if they do not actually aid in survival. Because the greater number of calories involved in building, maintaining, and using wing muscles also equates to a higher risk of death by starvation. Yes, that’s right, evolution by natural selection is essentially all about manipulating the actuarial tables. Can you decrease one danger without increasing another danger by the same amount?

But it’s nauseating to see that the iconic elephant tusk, a long-held adaptation used for defense against predators and in courtship displays is now becoming a liability in this way. Because, at least when it comes to those universal actuarial tables, the most important thing to know about tusks these days isn’t that it can fend off a lion, protect a calf, or impress a mate. No, the most significant thing about these wonders of evolution from a natural selection perspective is that some tacky, rich SOB wants an ivory ashtray. Now it is a race against the clock whether elephants can completely evolve away from tusks before poachers simply drive the species extinct.

That the fleeting fashion whims of humanity’s dregs should be producing an honest-to-goodness evolutionary pressure tells us that something has gone terribly wrong in our relationship with our planet. I fear natural selection will be hard put to keep up if we don’t reign ourselves in. Woe be to any species that tries to adapt to our changeable needs and wants.

Photo credit: Thinkstock

137 comments

lori c
lori c17 days ago

Noted - with sadness

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Cindy M. D
Cindy M. D18 days ago

It's so sad that elephants have to make changes to themselves to avoid the horrors of humanity.

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Bill S
Bill S18 days ago

This is very interesting. However by using drone technology to catch the criminal poachers the problem can be prevented.

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Leo Custer
Leo C19 days ago

Thank you for sharing!

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Georgina Elizab M

TYFS

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Leo C
Leo C20 days ago

Thank you for sharing!

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Amanda McConnell
Amanda M20 days ago

Thanks for sharing

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Amanda McConnell
Amanda M20 days ago

Thanks for sharing

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Cathy B
Cathy B20 days ago

Thank you for sharing.

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Kathy G
Kathy G20 days ago

Thank you

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