Rob Newman, Little Angel Theatre

There's a quite a contrast between the 12,000-seat Wembley Arena in 1993 where, with the help of his erstwhile writing and performing partner David Baddiel, Rob Newman “invented” comedy as rock 'n' roll, and tonight's venue, a bijou children's puppet theatre seating 100 patrons. But then Newman - Robert Newman to those who buy his novels - is doing rather different comedy these days.

That Wembley show was a collection of monologues and sketches (most famously History Today) with characters that had been created for their television series The Mary Whitehouse Experience (with Steve Punt and Hugh Dennis) and Newman and Baddiel in Pieces. After he and Baddiel parted company, Newman has made only the occasional foray into solo stand-up and has written a few novels.

Newman presents some quite complex theories with colourful and often surreal explanations

Now Newman, no longer sporting the chiselled cheekbones of yore and with the look of a kindly professor about him, has an unashamedly intellectual 90-minute discourse called The New Theory of Evolution - even if he can't resist a knob gag (and a very good one at that, worthy of his previous life) near the top of the show - and very entertaining it is too. His starting point is the belief that the selfish gene theory, as posited by Richard Dawkins and others, has been mis/used by some to excuse the dismantling of the UK welfare state and by others to paint a negative picture of humanity.

The famous non-God-botherer comes in for a mild kicking, even if “this isn't an ad hominem attack on Dawkins” (first time I've heard that phrase in a comedy show), and the comic's presentational style is warm and engaging. Like Ricky Gervais and Eddie Izzard, Newman presents some quite complex theories with colourful and often surreal explanations (animal language is a running gag) as well as anecdotes about his personal life and how he came to develop his theory, that altruism has been the distinctive marker of evolution.

Along the way, there are references to the great and good - Erasmus and Charles Darwin, Hans Christian Andersen, Richard Burton and Pyotr Kropotkin all get a namecheck - with stories about them I had never heard before. And as well as the multiple references to animal behaviour, such as how female buffalo vote on which way to roam and why vampire bats are decent coves, Newman makes some subtle political points; he has a very interesting suggestion as to how we can put poor but bright students to better use, for example.

Newman is not the brashest of performers - he stumbled over some lines or threw away others by mumbling - and the ending came with a fizz rather than a big bang as he picked up his ukulele-banjo for a song, never a good thing in my book. But there's no doubting the intellectual rigour as well as the solidly constructed comedy.

• Rob Newman is at the Little Angel Theatre, London N1 until 1 June, then touring until 12 December