Comet climax, clever corvids and cruel cats

We mark the demise of the Rosetta spacecraft and what it's taught us about comets, zoologist Rosie Hohnen tells us about the increasing impact of feral cats in northern Australia and how some native animals find shelter in rocky areas, and we find out about the incredible intelligence of corvids—that's birds like crows, ravens and Eurasian magpies.Watch some videos of these amazing birds below: