These Robotic Mice Are Programmed To...Uh...Mate.

Scientists at the Okinawa institute of Science and Technology are using a colony of mice-shaped robots with the express purpose sex with one another. Weird, robotic rodent sex. Yeah, on the list of phrases I never expected I'd write, that one ranks pretty high.

This isn't just the researchers being weird for the sake of doing so, mind you. There's actually a very specific purpose behind the robots: Polymorphism, an evolutionary and biological discipline which studies mating patterns and their influence on each successive generation of a species. In short, it's sort of a subset of evolutionary theory. The problem, of course, is that it can be incredibly difficult (and more than a little time consuming) to study the mating patterns of real-world animals in real-time. 

That's where the rodent robots come in.

The odd-looking little machines are going to be going at it almost non-stop over the course of several days, allowing the researchers to study an approximation of 1,000 generations of mice, and how each generation influences the and is influenced by the others. This will in turn help them to understand more about how evolution actually occurs, and how a species tends to adapt to its environment over generations. 

The robots themselves were designed by Dr. Stefan Elfwing, a researcher in the Okinawa Institute's Neural Computation Unit. Each machine in the colony is equipped with two wheels, a front-mounted camera to detect batteries and other robots, electrode 'teeth' to recharge from said batteries, and an infra-red port for 'mating.' After the robots were constructed, Elfwing then programmed them to simulate the evolutionary process, with each robot executing one of two types of behavior: foraging for food (batteries to charge from) or searching for a suitable mate.

Whenever one of the robots saw a potential partner it desired, the infrared port would flash to copy the mating partner's genes. Of course, whether or not the reproduction actually went through depended on how much energy each robot had. Some robots would thus substitute mating for the capture of energy sources, and vice-versa. 



See, according to the results of Elfwing's study, there were two types of mating strategies in his colony. The first was the tracker, which lied in wait for a mating partner which it would then approach. The second was the forager, which was wholly disinterested in mating unless it saw the face of a potential match.

There were over 70 experiments carried out with the robots, and over the course of these procedures 25% of the population was identified as foragers while 75% were trackers. According to Elfwing, the evolution noted in the computer simulations was very similar to what was often seen in the wild. Of course, this run around was a bit more simplistic - every robot was a hermaphrodite, capable of mating with any other robot it found.

"In the next stage," wrote Elfwing, "we want to see if the robots will take on male and female roles, by taking different risks and costs in reproduction. The behavior exhibited by the two strategies - forager and tracker - may be a precursor to the adoption of distinct genders." 

Who knew watching mechanical mice get busy could be so educational?