A number of submissions documented the effort species undergo to pass their genes down to the next generation. Michaël Nicolaï contributed a lovely image of a male frog perched on a stem, awaiting any females responding to his call (Additional file 5). Arnaud Badiane photographed two mating common wall lizards; Chris Darimont noted the “intense look from one of the lizards, presumably the male, with his limb thrown around the female” (Additional file 6).
A slightly different male–female relationship was captured by Maïlis Huguin in his image of a male and female spider entitled ‘Sexual Dimorphism’ (Additional file 7). As Chris Darimont put it: “Sexual Dimorphism—clear case of exactly that!”. Demonstrating that mating needn’t be all consuming, Jeroen Everaars photographed a female dancefly feeding on its prey while simultaneously mating with a male—who, seemingly precariously, keeps the three of them from falling to the ground (Additional file 8).
For the swallow-tailed gull, mating involves a substantial lifestyle change. The gulls spend most of their lives out at sea, only returning to land to breed. Majoi de Novaes Nascimento captured a gull perched high up on a cliff face at their breeding grounds on the Galapagos Islands (Additional file 9).
For many species, mating is the easy part; taking care of the resulting offspring is where it gets tricky. Roberto García-Roa captured this reality brilliantly with his photo of the frog Oophaga pumilio carrying its tadpole on its back, searching for a safe pool in which to deposit it (Additional file 10). The composition makes us appreciate the immensity of the rainforest compared to the tiny frog.
Producing young is normally the only job for ant queens, but as Julia Giehr’s colorful photo demonstrates, when they need to they will pitch into save their offspring (Additional file 11). Diogo Sayanda’s photo shows a male Abudefduf luridus trying—and failing—to save his eggs from a shoal of predatory fish (Additional file 12). Perhaps it’s wrong for us to find such an image so beautiful, but as Chris Darimont said “Oh—those gorgeous colors”!
For some species, reproduction and predation are one and the same, as with Cordyceps fungi, which parasitize insects in order to reproduce. The image ‘Fungus Attack’ (a third contribution by the very talented Maïlis Huguin) shows a butterfly parasitized in this way (Additional file 13). Chris Darimont felt the picture “captured the beauty (especially the colors) in an otherwise macabre process of decay. I also liked the apparent suddenness with which the moth expired, its feet seemingly glued by fungus to the leaf”.