In this lesson, students do a reading about R- and K-selection and then a gallery walk of four more unique reproductive strategies in animals. Students use the notes taken during the gallery walk to write a paragraph response comparing two different strategies.
The examples chosen include sequential hermaphroditism in clownfish and unisexual populations of all-female salamanders. However, they are limited in that all the example species are described to have binary sex. This lesson could be supplemented with examples of species where there are more than two sexes - see Scientific Evidence for examples.
Editor’s note: The term "hermaphrodite" is appropriate for referring to non-human animals with sex characteristics that do not fit typical binary notions of male or female bodies. For humans, “intersex” is the appropriate term—learn more here!
For a longer and more inquiry-based lesson, the gallery walk information could be shortened to remove the explanation for why each species has a unique reproductive strategy. Students could be tasked with hypothesizing the relationship between reproductive strategy and social structure or environment of the animal.