A reader writes, “I’m James Bernot, a graduate student studying shark and tapeworm coevolution at the University of Connecticut. Here is a tattoo I have on my calf of a Northwestern Pacific tribal shark, complete with a tetraphyllidean tapeworm near the shark’s pelvic fin.”

It’s hard for me to resist a tattoo of a shark tapeworm.

You can see the rest of the Science Tattoo Emporium here and in Science Ink: Tattoos of the Science Obsessed.

Originally published February 24, 2013. Copyright 2013 Carl Zimmer.

The Star Trek fans among you are no doubt familiar with “The Menagerie,” a two-episode story from the first season in 1966. The crew of the Enterprise gets trapped on a planet occupied by aliens called Talosions who look like humans, except for their massive, vein-encircled brains.*

That story was produced the year I was born, and when I saw it about a decade later, it made a big impression on me. Could brains get that big? Would they wind up with that cantaloupe shape? Would they provide Talosians with super-intelligence?

Continue reading “On the Possible Shapes of the Brain” →

When I talk about viruses, I have to struggle with big numbers.

If you get sick with the flu, for example, every infected cell in your airway produces about 10,000 new viruses. The total number of flu viruses in your body can rise to 100 trillion within a few days. That’s over 10,000 times more viruses than people on Earth.

Continue reading “An Infinity of Viruses” →

Paleontologists have found traces of animal life dating back at least 635 million years. Those earliest animals may have been like today’s sponges, rooted to the sea floor and filtering food particles from the water. Over the next 100 million years or so, new kinds of animals emerged. Some were recognizable members of living groups of animals, while others were so bizarre that paleontologists suspect they belonged to long-extinct lineages. And then, around 520 million years ago, the fossil record of animals starts to roar like a firehose switched from a trickle to full blast. Many of the oldest known members of living animal groups–including our own–appear during the Cambrian Period. But the Cambrian fossil record is also rife with forms only distantly related to animals on Earth today, some of which were so weird that the sight of a reconstruction of the creatures made scientists burst out laughing.

Continue reading “The Weird Youth of the Animal Kingdom (Slide Show)” →