The team found that the birds counted from the left, preferring to go to a dispenser fourth from the left, not the right (Biology Letters, DOI: 10.1098 / rsbl.2009.0960). (newscientist.com)
Two - thirds of the chicks approached the possible cube rather than the impossible one (Biology Letters, DOI: 10.1098 / rsbl.2011.0051). (newscientist.com)