Brain Parasites Make Their Way Into Shell-Bound Baby Lizards

Scientists found parasitic worms in the brains of lizard embryos. How did they get there?

Transcript

00:00 Scientists found parasitic worms inside the brains of lizard embryos

00:05 before the animals ever hatched.

00:07 How did they get there?

00:09 It turns out that these parasitic worms hide out in the ovaries of the lizard's mothers

00:18 and then make their way into the developing embryo

00:21 before a hardened shell forms around the animal.

00:24 The scientists that found these worms believe this is the first time

00:27 a parasite has been found that passed from a mother reptile into its offspring.

00:33 This has been found in mammalian species

00:37 where a parasite can either pass through the placenta to the developing animal

00:42 or it can be passed on through the breast milk after birth.

00:45 Because this sort of parasitic transmission hadn't been seen in reptiles before,

00:49 scientists thought that by laying eggs,

00:52 reptiles actually restricted the number of ways that parasites can get into their young

00:56 so they'd have to wait until the animals actually hatched before burrowing into their brains.

01:02 But after making the shocking discovery of these worms inside lizard embryos,

01:07 scientists now think that reptilian embryos might be more vulnerable to parasites than once thought.

01:13 But they don't yet know how these worms might affect the animals' health and behavior after they hatch.

01:19 (Music)