1/5. How did the elephant get so big? Chris Packham explores the four-billion-year story of how a tiny cell evolved into complex, gentle giants. Also in HD. [S,AD,SL]
3/5. How did the bat get so hungry? Chris Packham explores how the drive to find food has shaped animal life. The origin of bums, guts, jaws and super-hearing. Also in HD. [S,AD]