Now that I've finalised 2/3 of the manuscript for my new book, I'll reveal the title of the book (well at least the title I have suggested, there is always the risk that some marketing guru decides we need to use a different one!):

It's:

The birds, the bees, and the platypuses

and it comes from a story about the sex chromosomes of the duck-billed platypus (obviously), which will also be featured in the book. The story does mention birds and bees as well, so I didn't make up the title just for the fun of it ...

More details when I've finished the last third ...