If you asked me about cosmology, I’d defer to physicists — I’ve read Stenger & Hawking & Krauss & Carroll, and I might be willing to say a few generalities about what I’ve learned about the process, but I’d always say you should look to the original sources for more information.
There seem to be a lot of physicists, however, who believe they know everything there is to know about biology (it’s a minor subdivision of physics, don’t you know), and will blithely say the most awesomely stupid things about it. Here, for instance, is Michio Kaku simply babbling in reply to a question about evolution, and getting everything wrong. It’s painful to watch. This guy isn’t really an idiot, is he?
Man, he doesn’t have a clue and is just making it up as he goes along.
Fundamental error: he confuses evolution with natural selection, and thinks that if we aren’t being hunted down by sabre-toothed cats, evolution has stopped. This is wrong. We currently have reduced mortality compared to our ancestors, which suggests that we are less strongly selected in specific ways, but we are still experiencing selection — some of us have been selected for lactose tolerance in the last 10-15,000 years, for instance, and sexual selection is ongoing, and in case you hadn’t noticed, there are still diseases around that kill people.
But most importantly, reducing mortality and selection allows variants to survive, increasing the diversity of forms present in the population. You could even argue that reducing selection increases the rate of evolution. Selection is a conservative force that retains only a subset of the population for propagation into the next generation, you know.
And the rest: “gross” evolution? What the hell is that? Creationists already mangle the distinction between micro- and macro-evolution, now all I need is some half-assed third category getting peddled by the ignorant. And where does he get this idea that Australia is the product of accelerated evolution? That makes no sense at all; isolation meant the populations there evolved relatively independently of forms elsewhere, not that something goosed their mutation rates.
Oh, look: somebody in the comments asks Kaku about why we only use 20% of our brains. Let’s hope the next time he answers a reader question, he’ll tell us at length what we can do with the sleeping 80% of our brains. (I use mine for fulminating at morons, how about you?)
Actually, I’d rather he tried to answer the question in the title of this post.