Idle Thoughts?

As we humans hustle through our days occupying our thoughts with whatever it is we think about during our daily routines, a particular project we’re working on, what to eat for lunch, or whether to go to the mountains or to the beach the coming weekend, we unknowingly pass by a myriad of creatures sharing our world whose thoughts, if they have them, are far less abstract and more consequential to life itself. What creatures?

Stop and have a look around you. Take some time and watch what’s going on. Follow that bird’s flight into the shrubbery. Turn over a leaf. Investigate the “bug” crossing the sidewalk.

Down near the Red Wolf Enclosure in Explore the Wild, I’ve been keeping an eye on a brown thrasher’s nest. I watched the long-tailed birds with rich brown upperparts and white, dark streaked breasts build the nest. I saw them sitting on eggs in the nest. And, I’ve been observing the adults fly into the nest site with beakfuls of food for the nestlings.

Brown thrasher sitting on eggs.

The nest is not obvious to the casual passerby, but it’s only two or three feet off the path and nine or ten feet off the ground in a vine covered red cedar. If you stood on the path in front of the wolf enclosure for a minute or two you might see one of the adults fly into the tree in which the nest is located, and then scurry over the branches to the nest. There’s little time for leisure for these birds while they hunt for insects to feed their young.

Three nestlings and one adult in this shot.

Brown thrashers are mimic thrushes, related to mockingbirds and catbirds. They mimic other bird songs or sounds in their environment. The best known of the three mimics, mockingbirds, have a huge repertoire of sounds employed in their songs. The songs seem to go on forever, and, to the dismay of light sleepers, often continue well into the night. Catbirds have a sizable cache of distinctly squeaky phrases in their songbooks which may or may not include the meow of a cat. The brown thrasher’s sweet song too consists of a long list of phrases. Besides the melodious quality of their song, they usually repeat each phrase twice before moving on to the next phrase. The catbird’s song is squeaky. The mockingbird, sweet and unending. The thrasher’s song is sweet too, but with repeated phrases.

Another thrasher nest can be seen in a magnolia tree in Hideaway Woods.

There’s a small patch of dogbane, or indian hemp, just next to the entrance path to the Lemur House here at the Museum. Dogbane is toxic. The stems and leaves contain a milky latex, a toxic glycoside. Despite the toxins, or because of them, the plant attracts many insects. One in particular is the dogbane beetle.

Mating time for dogbane beetles.

Dogbane beetles spend their entire lives on or around the plant. The beetles eat the leaves of the plant. They lay eggs on the leaves. When the eggs hatch, the larvae fall to the ground at the base of the plant. They burrow into the ground and consume the roots of the plant. They pupate below ground, emerging the following spring as adults to begin the cycle anew. Dogbane is their life. I’ve read that they will eat milkweed too, though I’ve never seen a dogbane beetle on milkweed.

If you happen to pass a patch of morning glory and notice holes in the leaves, stop and have a closer look. Turn over a leaf or two, you may be surprised at what you see. If you’re lucky, you’ll see a golden tortoise beetle. The banner photo at the top of this post and the one below are of a morning glory leaf complete with holes and beetle. Golden tortoise beetles eat morning glory leaves.

Golden tortoise beetle.
Beetles turn red when disturbed.

The tortoise beetles have transparent elytra. Elytra are the folded forewings of a beetle. The forewings are what make up the hard “back” of the beetle when not in flight.

If you disturb the beetle, which you may do by turning over a leaf, it will likely change color from golden to red. It’s yet to be determined what causes the color change in this species (Charidotella sexpunctata) but a relative of the golden tortoise beetle has been found to change color based on liquid levels within the elytra, saturated=gold, dry=red.

It was large enough to see at thirty yards distance. A spider was crossing the path in front of me, a large black spider. As I got closer, I could see that it was a trapdoor spider. The nearly round abdomen, short legs, and flat shield-like “plate” over the cephalothorax gave it away.

Trapdoor spider.

Trapdoor spiders dig holes in the ground covering the hole with a silken lid. They lay inside the burrow, lid down, waiting for insects and other prey to wander by, at which time the lid flies open, the spider lurches out and snatches the prey below.

Missing a leg and pedipalp.

The pictured spider is missing its left front leg and pedipalp. Did it have an encounter with another spider? a prey item larger and more powerful than anticipated? or perhaps a human?

It’s barely summer and fall webworms are busy at their industry. One was spotted on a handrail of the boardwalk leading into the wetlands in Explore the Wild. Soon, they seemed to pop up everywhere. I found them on redbud, boxelder, black willow, and mulberry.

Fall webworm.

Unlike tent caterpillars which construct a webbed “tent” in the crotch of a tree, making forays out to the leaves of the tree to feed, webworms build their “tents” around the leaves they’re actively feeding on. They expand their webs outward as they consume the leaves within. Tent caterpillars are restricted to the spring. Webworms can be seen well into fall, sometimes covering entire trees with their silken webs.

Webworms protected in their web.

I don’t know if any of these creatures have the time, or even the ability, to think about and visualize such things as what’s for lunch, or where to spend the weekend, but there must be something going on inside their little brains or simple nervous systems. After all, they build nests, dens, or burrows. They know when and where to find food. Is it all simply reaction to stimuli? What’s going on?

I can’t say what birds or insects are thinking, if they think at all, but I know it’s interesting watching them do whatever it is they may or may not be thinking about. It sure sets me to thinking.

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