It is a fantastical tale that transports us through space to California, and through time, some 1.23 million years back. Its heroes, twigs, are disguised as leaves. Yet, they move! The English-speaking world calls them stick insects, while the French more commonly refer to them as phasmes. The star of our story is one of their 3,100 species.

Long, long ago, a small mountain on the west coast of the American continent split into two mounts separated by a valley about 30 kilometers wide. These two mounts, Refugio and Highway 154, now stand near the city of Santa Barbara, covered in a coastal chaparral ecosystem of brush and shrubs.

On each of these mounts lived two forms of this stick insect, which would much later be named Timema cristinae. Like all their cousins, these wingless insects perfectly mimicked the leaves they feasted on. An ideal camouflage to deceive their predators and safely feast.

One form delighted in the broad, dark green leaves of the California lilac (Ceanothus spinosus). Its counterpart preferred to savor the very thin, needle-shaped leaves of a rosaceae, Adenostoma fasciculatum.

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