Week 17: your baby is the size of a star-nosed mole

Your fetus is now the size of a star-nosed mole, a roughly 13 cm burrower with the strangest nose in the animal kingdom: a ring of 22 pink fleshy tentacles that ripple constantly as it explores.

That star is not for smelling. It is a touch organ, packed with more than 100,000 nerve endings in an area smaller than a fingertip. It is the most sensitive touch organ known in any mammal, and it lets the mole identify and eat prey in under a quarter of a second.

The star-nosed mole is also the fastest-eating mammal ever recorded. It can detect, catch, and swallow a food item faster than the human eye can follow. It even blows bubbles underwater and re-inhales them to smell prey while submerged.

Meanwhile, inside you

Your fetus this week is developing their sense of touch in earnest, and is starting to build up a layer of brown fat that will help keep them warm after birth.