Virologist Marion Koopmans is one of the independent researchers appointed by the World Health Organisation to investigate the origins of the coronavirus pandemic. The team visited China in January this year as a first step to answer how, when and where SARS-Cov-2 first infected humans. Professor Koopmans tells Victoria Gill that time is beginning to run out to launch the next phase of studies, to trace the first people in China to be exposed and identify the animals from which the virus jumped the species barrier.

Also in the programme:

Is the practise of feeding the birds in our gardens creating losers as well as winners, and causing the numbers of some woodland birds to decline? Conservation biologist Alexander Lees visits Victoria in her garden to discuss the question, and reveal the truly dark side of the Great Tit.

A new study of the impact of street lighting on nocturnal insects shows that the local impacts on moths can be dramatic. According to entomologist Douglas Boyes, street lights deter female moths from laying their eggs and make them more vulnerable to predation by bats. He's found that artificially illuminated areas are home to half the number of moth caterpillars compared to dark areas.