Highlights of 2009: Radio

Lily Allen's second album, Jude Law as Hamlet, Michael Sheen as Brian Clough, Martin Amis on feminism – 2009 promises a variety of treats in the arts. Our critics predict what will make waves in the coming months

Every year there are anniversaries – well, obviously – but some years they get more attention than others. Radio 3 is preoccupied all year by four big ones, what they're calling their "Composers of the Year": Purcell (born 1659), Handel (died 1759), Haydn (died 1809), and Mendelssohn (born 1809).

Apart from a series of big weekends and concerts, there will be complete cycles of Handel's operas (every Thursday for the whole year apart from the Proms season) and Haydn's symphonies (two a week, all year). The Handel and Purcell events also form part of a wider festival, "Baroque '09" – fine, if you like Baroque.

Centenaries are mostly outside Radio 2's remit, but it is getting in on the act with a slew of documentaries marking a couple of half-centuries: it's 50 years since Motown was founded; more depressingly, 3 February 1959 was the day the music died – when Buddy Holly, Ritchie Valens and the Big Bopper died in a plane-crash in Iowa – which is the perfect excuse for a month-long Fifties season.

The big non-musical anniversaries are both to do with Charles Darwin, who was born on 12 February 1809, and published On the Origin of Species in 1859.

A whole year wouldn't be enough to explore the difference he made to the way we see our place in the world – evolution being what the American philosopher Daniel Dennett called a "universal acid", dissolving everything it touches – but Radio 3 and 4 are both promising to make a start.

And one more anniversary, which isn't quite as big as it should be – Alfred, Lord Tennyson, born 1809, author of at least half a dozen of the greatest poems in English (that's not including "The Charge of the Light Brigade" or "The Lady of Shalott"): readings, features and dramatisations will appear on Radios 3 and 4 in August, the month of his birthday.

But for many, the biggest thing will be the tiny changes: Jo Whiley back on Radio 1, and a schedule shift on Radio 4 from January: Saturday night's Archive Hour will be repeated on a Monday afternoon, Gardener's Question Time on a Friday, with Afternoon Readings pushed out to make room. This is the kind of innocuous-looking alteration that drives Radio 4 listeners out on to the streets, overturning cars and throwing Molotov cocktails.

I hope Mark Damazer, the network's controller, is wearing his hard hat.