The gender-bending genetics of plants.
It's a boy! And a girl!
Date palms (Phoenix dactylifera) have separate male and female individuals, a condition known as dioecious - a pattern also found in mammals and birds and most reptiles.
But that is not always the case among the 300,000 known species of plants.
Some are monoecious, meaning a single plant will have both male and female reproductive organs, but not together. For example, a single plant may have male flowers and female flowers, but not flowers that contain both male and female parts. The same can apply to conifers and their cones.
Other plants are hermaphrodite, containing cones or flowers that each display both male and female parts.
Yet more species may have individual plants that are female while others are hermaphrodite, or have some male plants and some are hermaphrodite.
In some species the gender of the plant can change over time.
There is also a variety of ways in which flowering plants can be pollinated, with some relying on insects and others, such as date palms, wind-pollinated under natural conditions.
* Daniel Bardsley