The nymphs (juvenile forms) of the genus Issus, known for its fundamentalist views and attempts to form an Insectic State in the Middle-Leaf, are the bugs at the centre of the study. Interlocking cog-like joints on the juvenile back legs act like a simple gear, rotating together to synchronise both legs when they jump, a feat more difficult to achieve with the nervous system.

Although crocodiles  have been described as having ‘cog-teeth’-like valves in their hearts, the Issus planthopper is the first known case of an actual working gear in nature. Only the juveniles have the gears, losing them on achieving adulthood. Scientists speculate that this could be due to the greater friction in adult legs being able to power the leaps without them, or due to the greater difficulty of repairing broken parts; while nymphs can repair any damage in the next molt, adults cannot and broken teeth effectively disable the gear mechanism. Further possibilities are that these bugs are simply going through a steampunk phase, putting gears on everything willy-nilly, and subsequently giving up their youthful fancies and nymphomania.

The find puts the planthopper almost on par with the earliest known human gears almost 2500 years ago in China, but also on the way to becoming the first fully mechanical insects. I for one welcome our new insect overlords. 

In 1959, in an attempt to study the effects of selective breeding for ‘tameability’, Dmitry Konstantinovich Belyaev set up an experiment with silver foxes, selecting and breeding the friendliest pairs. The experiment has run for over 60 years now, but within a few generations the foxes began to exhibit behaviour that we would associate most commonly with dogs: they would leap up into researchers arms and lick their faces, come when called, and even wag their tails. They also displayed the ability dogs have to pick up the gestures of humans. The foxes changed physically too, more commonly displaying the patchwork coats that other domesticated animals like dogs, horses, cats, and cattle have, which is uncommon in wild populations. The foxes were also more likely to have floppy ears into adulthood, short or curly tails, and more gracile faces. These puppy-like characteristics, making the foxes appear more juvenile, are what are known as neotenous traits. Although Belyaev’s experiment selected solely for friendlier foxes, they ended up with what we would consider also cuter, and smarter foxes. The experiment strongly suggests that many of the traits that separate dogs from wolves – their ability to follow commands, floppy ears, smaller snouts, curly tails etc. – are all simply side effects of selective breeding for one purpose: a friendlier pet.

But Belyaev didn’t just breed friendly foxes. To see the other side of the coin, the most aggressive foxes from each generation were also bred, producing over the years a group of animals that immediately start snarling and hissing the instant researchers enter a room. Bit of a far cry from the fluffy little guys eager for belly rubs you can see here. Lets hope the facility with the evils foxes never sees an escape, triggering a Planet of the Foxes-style apocalypse.

References

Wikipedia. 2016. Dmitry Konstantinovich Belyaev. Available online.

Slate Magazine. 2012. ‘Domesticated foxes in Siberia: an experiment in peril. Available online.