Is the rate of human evolution increasing with population growth?

Larger populations create more chances for genetic mutations to occur, and this means more variations for natural selection to either favour or weed out. But in big populations, it takes longer for chances to spread. The fastest rate of evolution occurs when a population is split into isolated subgroups that can’t interbreed due to geographic or cultural barriers. Travel and communication have broken down many barriers, so our genes get blended together instead of splitting into subspecies. A 2007 study found that we are evolving about 100 times faster than at any other period in our history. But ‘modern’ for an evolutionary biologist means the last 5,000 years. It’s too soon to tell how our evolution has been affected by the population explosion of the last few centuries.

Could robots be programmed to evolve?

Yes. In research that was published in some time ago, teams in Cambridge and Zurich built robots that evolve through successive generations.

The ‘mother’ is a robotic arm that builds ‘baby’ robots out of small cubes. Each cube has a mechanism where one side can waggle. When you place it on a surface, it clumsily drags itself around. The mother glues these moveable cubes together in various arrangements. Some combination move further and faster than others. The mother robot builds each arrangement using assembly instructions in the form of a ‘genome’ that is passed between successive generations of robots.

The mother is programmed to insert random mutation into each generation. Some offspring move around better than their forerunners, but others do worse. The mother rejects deficient generations but uses the genetic blueprints of successful ones to build subsequent offspring. In the lab, after only 10 generations, the robots performed twice as well as those at the start of the process.

Why do people cheat?

Because they want to win the easy way. As competitive animals, we human beings constantly seek out opportunities to gain money, food and sex, or simply to look good. Doing all this the hard way requires expenditure of time,efforts and energy, so cheating can obviously be very tempting.

Evolutionary game theory has helped to explain how altruism can exist alongside cheating. Generally, cheats do well when they are rare, but less well when they are many and have fewer non-cheaters they can exploit. So groups tend towards an equilibrium, with few enough cheats that it’s not worth the cost of stopping them. Sadly, this basic biological principle means we are unlikely ever to be completely free of cheats.

WHAT  IS  THE  MAXIMUM  NUMBER  OF  NAMES  A  PERSON  CAN  REMEMBER ?

There’s no known limit! If you ask a mnemonist or memory savant to learn a list of names they may remember thousands, tens of thousands or even hundreds of thousands with no trouble, just as they can learn lists of thousands of digits. Some people who have a neurological condition called ‘hyperthymesia’, remember everything that happens to them every day, including the name of every person they have ever met.

The rest of us evolved to cope with no more than about 150 social relationships. This is known as Dunbar’s number after the anthropologist Robin Dunbar. He discovered that groups of hunter-gatherers, units in armies, divisions in businesses and many other groups tend towards a limit of 150. And it seems that social media do not change our basic nature. Even people who have thousands of ‘friends’ on Facebook rarely maintain more than 150 meaningful relationships.