Scientists have found that some plants like the humble corn display altruistic behaviour just like animals.
The study led by the University of Colorado Boulder looked at corn, in which each fertilised seed contained two "siblings" - an embryo and a corresponding bit of tissue
known as endosperm that feeds the embryo as the seed grows.
They compared the growth and behaviour of the embryos and endosperm in seeds sharing the same mother and father with the growth and behaviour of embryos and endosperm that had genetically different parents.
"The results indicated embryos with the same mother and father as the endosperm in their seed weighed significantly more than embryos with the same mother but a different father," said Professor Pamela Diggle, a faculty member in CU-Boulder's ecology and evolutionary biology department.