It was an awesome and humbling experience hiking in Baja California with expert biologists. I felt as if I had walked into a high school reunion where nobody was wearing badges. Everything looked vaguely familiar, but no matter how hard I tried I couldn't summon up names for the plants and animals. However, for the scientists walking on the same trail, everything was an old and familiar friend.
Of course I might be excused because so many of the plants and animals we saw were restricted to Baja, or in the parlance of biologists “endemic.” Some species were endemic to the southernmost Cape region of Baja California, some to the nearby mountain ranges, but they're still unique to the area. In fact, nearly a third of the plants on the Baja Peninsula are endemic. To get a rise out of us, Botanist Jon Rebman had to start pointing out endemic genera—a higher level and rarer form of endemism.
And if our minds weren't already reeling about the nature of diversity in Baja, Jon would start spinning stories about pollination and seed dispersal. Like all living creatures, the ultimate goal of plants is to reproduce. Sedentary plants have evolved many ways to use animal assists. There are plenty of bees, butterflies and hummingbirds (for example the striking and endemic Xantus's hummingbird) that visit flowers for nectar—and transfer pollen in the process. In Baja California, hummingbirds pollinate a wide range of flowers including some cacti and a mistletoe.
But it gets crazier.
One of the favorite things I learned was about an inconspicuous vine hovering near the ground on the side of the trail, Aristolochia watsonii (pictured above). Its flower looks like a mouse’s ear. It even smells like a mouse. Small biting flies enter the flower looking for mouse blood. They follow hairs that point down toward the “ear canal,” and are trapped overnight. After milling around in the pollen for hours they are finally free in the morning when hairs on the flower switch their direction, allowing the flies to walk out. Once free, they move on to another fake mouse ear, depositing the pollen from the last flower.
Animal pollination is only part of the story. Some plant species have the option to reproduce asexually, and some have male, female, and hermaphrodite flowers. Mind-boggling doesn't even begin to describe it. So my advice for Baja newbies is to tread carefully—and keep a botanist nearby.
Tarantula hawk wasp visiting milkweed. Photo by Bud Ferguson.
Xantus's hummingbird. Photo by Bud Ferguson.
Jon Rebman spotting Aristolochia watsonii.
Aristolochia watsonii. Photo by Jon Rebman.
Jon Rebman explaining asexual reproduction in chollas.
Stenotis australis, a genus endemic to Baja California Sur. Photo by Jon Rebman.
I was fortunate to have Botanist Jon Rebman (left) and Ornithologist Phil Unitt as guides.
Posted By President and CEO Judy Gradwohl.
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