Bees - Nearly all bees in the UK suffering serious declines. They're mostly threatened by habitat and land-use change. But disease also plays a part. Adam Rutherford talks to Professor Mark Brown about new work he's done looking at the evidence of diseases harboured by honeybees, spilling over into wild bumblebees.

Pain and epigenetics - Marnie Chesterton goes to Kings College, London to watch identical twins being tested for pain tolerance. The study is to gain insight into the genetic components of pain perception. One area which is fascinating researchers like Professor Tim Spector is the role of epigenetics in how we process pain. Our epigenome is a system that changes the way our DNA is interpreted. Genes can be dialled up or down, like a dimmer switch, by adding little chemical tags to the DNA. These chemical tags, unlike DNA, are changeable, in response to the changing environment. So could the way we live affect the pain we feel?

Whales from Space - More listeners' questions, this time, asking whether surveys using images from satellites to see whales underwater, could be hijacked by whale hunters? Peter Fretwell from the British Antarctic Survey has the answer.

Genetics of sexual preference - The media is all of a twitter this week over unpublished work recently revealed on research looking for genes related to homosexuality. We hear from Professor Tim Spector on the topic, and Adam talks to Professor Steve Jones about the science.

Producer: Fiona Roberts.