Mold & Management

Staff Writer
Columbus Alive

01:: They both respond to external stimuli

Slime mold (Dictyostelium discoideum) can, and does, move (a fact responsible for the notorious B-movie The Blob). The movement is known as chemotaxis because the slime mold senses a chemical (chemo) and moves (taxis).

To understand the directional nature of the movement, think of freshly baked chocolate chip cookies and a skunk's smell. Anything the slime moves toward is a chemoattractant. If the mold moves away, the substance is a chemorepellent.

Just as you follow the aroma of cookies to the kitchen or flee desperately from the skunk's spray, slime molds detect chemical gradients to determine the direction of their motion. Either the mold goes toward the higher concentration of an attractant chemical, or it slithers toward lower concentration if the chemical is a repellant.

02:: They're both eukaryotic

There are two basic cell types. Prokaryotic cells have an external membrane, and all their other parts float in the cytoplasm within it. Eukaryotic cells have an external membrane as well, but they also have smaller membrane sacks inside. The sacks are called organelles, and each kind of organelle is specialized for a different function.

Slime mold and your boss share this quality. Not only do they both have organelle-containing cells, they also have the same kinds and similar numbers of each type of organelle.

03:: They both reproduce sexually

This is true for humans, certainly, since a sperm and egg must fuse to get things started. That fertilized egg, or zygote, will go on to divide thousands of times to develop the human body.

For humans, there's the hope of happily ever after, but not for slime molds. Once two swarmer slime mold cells fuse, the new cell goes on to divide two, and only two, times to produce four daughter cells. Each of these cells is a swarmer that can either remain solitary or clump with hundreds of others to form a slug.

This mold can even do something your boss can't - reproduce asexually by having one swarmer cell divide in half to make two identical clones. Let's hope the boss never develops that ability!

Adapted from Condensed Knowledge (HarperCollins), which is available at leading bookstores. For a daily dose of quirky fun, visit and check out mental_floss magazine at your local newsstand.