Selected by Nature's photo team, the month's sharpest science shots include a significant milestone in saving a species.
A southern white rhinoceros foetus was the result of the first successful rhino embryo transfer into a surrogate mother through in vitro fertilization (IVF).
Witnessing the milestone in saving a species "was something I will never forget", said photographer Jon A Juárez.
Although the embryo did not survive due to an infection, the breakthrough paves the way for saving the rare northern white rhino from extinction.
Author's summary: IVF offers hope for saving the northern white rhino.