Super-senses in the Animal Kingdom

Sophia Akiva

Some hold the belief that humans were made in the image of an omnipotent being, while others consider us to have adapted through evolution to become the dominant species on our planet. The debate between these views is best left for another time, but for a species that has no natural predators, can survive on all seven continents and has built technologically advanced civilisations, our sense of superiority over our four-legged cousins is well justified. Yet still we yearn for more, imagining superheroes with inhuman abilities and senses, taking inspiration from the very creatures we consider to be less than us. Our brains may be better developed when it comes to reason and logic, and that in itself can be considered a superpower, but the animal kingdom is filled with creatures that have brilliant powers of their own.

First of all, let us consider eyesight. Human vision is very advanced and adapted perfectly to the peak wavelength of sunlight we receive through the atmosphere, however as soon as the Sun sets we are left at a disadvantage. Animals like tarsiers on the other hand, are not. These tiny adorable creatures are also deadly predators, being the only primates to be fully carnivorous, and responsible for this are their super-sensitive eyes.

Unlike other nocturnal creatures, tarsiers do not have a reflective layer behind their retinas and so are unable to bounce faint light through them twice in order to absorb it. To compensate for this, their eyes have grown to colossal proportions relative to their small body size, with each eye being approximately the same size as the brain, which itself has grown large in areas responsible for processing all the visual information thus received. As well as turning these little mammals into perfect hunters, their incredible sight is also used to traverse the canopies in the night and to defend against predators, who are often attacked by one or more groups of tarsiers upon being detected.

The animal most famous for having incredibly powerful eyesight is the eagle. Not only can they see much further than a human but the images their brain interprets are of higher resolution due to a greater number of light-sensing cone cells within the retina. The range of light frequencies they can detect extend beyond visible light and into the ultraviolet, an ability that is also shared by a completely different creature, the mantis shrimp. This crustacean can show off an even more impressive eyesight than its feathered peer, with up to 16 visual pigments compared to five in the eagle and our own measly three.

Juvenile_Bonelli's_eagle wikipedia.jpg

Image Credit: Wikipedia

Like the two animals mentioned above, the mantis shrimp also uses its superhuman power to hunt down prey but is different in having the additional ability to identify the polarisation of light it detects through eye movements and distribution of cones. But it doesn’t end there, with their survival resting solely on their vision, these creatures have developed a way to insure it. This comes in the form of binocular vision, which is necessary for many predators, present independently in each eye of the mantis shrimp! So if they ever lose an eye, their depth perception would remain uninhibited. With so many processes going on within the eyes at the same time, the information has to be analysed by the eye itself before being transferred to the brain.

Let us now move onto the super sense of touch, which brings with it an introduction to another majestic predator of the animal kingdom, the star-nosed mole. This mammal is often rudely listed as one of the ugliest animals on Earth due to the tentacles extending from its snout, which are densely packed with sensory receptors and allow it to feel the movement of its prey. This specially adapted snout serves a second purpose of keeping soil from entering the mole’s airways as it burrows through its network of underground tunnels. This habitat has driven the development of such superb sensitivity in one sense, yet has caused the mole to lose almost complete use of another, leaving these animals practically blind.

Another animal  that appears to have sacrificed one sense to become the master of another is the snake, however their deafness in a long standing misconception. Although they do not possess sound detectors outside of their body, they are still able to process auditory information from the vibrations they pick up from the ground. This is the same mechanism they use to process their own super sense of touch. Snakes are able to differentiate the vibrations passing into their skeleton from the ground as either sound or mechanical and so the signals are passed through different sensory organs and processed by different parts of the brain. But the magnificence of the serpent doesn’t end there, their sense of taste is also superhuman. The famous forked tongue of the snake not only allows the animal to detect its prey, but also to determine the direction from which it is coming.

The animals discussed here are just a few examples of the vast variety of fascinating creatures that possess incredible sensory abilities, many of which are still currently being researched. We humans are not without our own merits. We may not be able to spot a rabbit from two miles away but we are the only species on Earth to have gazed upon the surface of Pluto – so perhaps our intelligence really is a superpower after all.

We Might Be Able To Save Predators And Livestock At The Same Time.

Katy Drake

The debate is ongoing; should lethal or nonlethal predator control methods be used to protect livestock? According to logic, if predators are killing livestock, by removing those predators, livestock losses should decrease. However, as there are legal, ethical and ecological risks at stake, common sense may no longer pass as sound justification.


Image credit: wallpapercave

Research, led by Associate Professor Adrian Treves of the University of Wisconsin, Madison, and published in the Frontiers of Ecology and the Environment, examined more than one hundred peer-reviewed studies of predator control methods and livestock in Europe and North America. Yet, of the over one hundred studies analysed, only twelve met the academic standards from which scientific inference could be drawn; with two reaching ‘gold standard’ and the other ten, a lesser ‘silver standard’.

The results from the twelve studies examined, suggest nonlethal methods of predator control are generally more effective and do not lead to counterproductive consequences.

A variety of predator control methods are used by livestock owners. Lethal methods include hunting, poisoning, kill traps and destroying the litters of young. Nonlethal methods include livestock-guarding animals, fladry (visual deterrents), other types of repellents, fences, diversionary feeding and sterilisation.

Of the one dozen studies analysed, seven examined lethal methods of predator control; two of which appeared to conclude a decrease in livestock loss but only to a minor degree and on a short term basis. In one particular case, it was found that less than one lamb was saved per lynx killed and had negligible practical benefits.

The remaining five lethal method studies concluded either no effect or, in two cases, an actual increase in predation. A study published in 2013 determined that killing cougars resulted in detrimental effects to livestock numbers. Older, male cougars would keep the younger, more aggressive males at bay. Consequently, the hunting of older males, resulted in the immigration of younger males and increased livestock loss.

By contrast, not one of the nonlethal method studies showed an increase in predation. Of the twelve studies examined by Treves and his colleagues, the only two that met ‘gold standards’ examined nonlethal methods which effectively decreased livestock losses through the use of livestock-guarding dogs and fladry, although fladry may be limited to deterring wolves.

One long term and in-depth study, conducted in France, concluded that a combination of mobile electric fences at night and at least five livestock-guarding dogs prevented almost all wolf predation on sheep.

Treves’ critics have suggested that his own study may not be living up to his standards as no independent experts were asked to review the validity of his research. They also suggest that Treves’ expectations of academic standards in predator control research may be impractical as complexities in the field of biology result in most ‘gold standard’ experiments being precluded.

So, what does this mean for the future?

Treves and colleagues have called for a suspension of predator control programs that do not have strong evidence to support their efficacy. They suggest that, like the EU Directive and many U.S. Federal policies, decision-making should be based on clear evidence and as such, until ‘gold standard’ tests have been completed, evidence-based policy should focus on nonlethal methods. However, a major culture shift will also be required amongst ranchers and livestock owners to turn from quick and easy lethal methods to nonlethal predator control.