black widow must Despise Clint Sergi. During his PhD in biology from the University of Wisconsin-Milwaukee, Sergi spent time designing small challenges for spiders. This often included feeding the spiders delicious dead crickets or stealing crickets to confuse them. “The big question that motivated the research was wanting to know what was going on in the minds of animals,” he says.
Biologists already know that spider brains are different from human brains. Their sensory world is tuned for living in cobwebs and dark corners. “Humans are very visual animals,” says Sergi. “Most of these web-building spiders number Vision. They have eyes, but they are mostly adapted to sensing light and movement. Instead, the Black Widow’s perception comes primarily from vibrations, much like hearing.
As for cognition, biologists know that these spiders remember when they have caught prey. Some scientists, including Sergi, even believe they form mental representations of their own webs. Little is known about how it affects So Sergi and his advisor and spider cognition expert Rafa Rodriguez decided to test the memory of black widow spiders. As you can imagine, Sergi offered the spider a dead cricket, stole it, and returned it.
As a result they wrote in a journal animal behavior, indicating that black widows have better memories than previously known. Letting prey escape, the spider repeatedly searches for a niche. In some cases, they seem to remember the size of their prey and are looking for more of the biggest snacks stolen. “They don’t just respond to certain stimuli with fixed patterns of behavior,” says Sergi. “They have the ability to make decisions.”
This study serves as a reminder that complex cognitive computations are prevalent in the animal kingdom. Internal navigation systems, including those that rely on very different sensory inputs, have been shown to manifest in both the cerebrum and the microbrain. “We show that arthropods can encode the complex memories often associated with vertebrates,” said Andrew Gordas, a behavioral neuroscientist at Johns Hopkins University. “Invertebrates are much more sophisticated than we believe.”
Add Sergi result There is growing evidence that insects and spiders form and act on detailed memories similar to humans, but in very different ways. We orient ourselves using hippocampal ‘place cells’ that arthropods lack. Still, says Gordas, “they have brain regions that have evolved to perform the same functions.”
The central nervous system includes the spinal cord and the 3-pound brain. The spider has her two clusters of neurons called ganglia. One above the esophagus and one below the esophagus. A key input for this brain comes from thousands of sensors along the spider’s exoskeleton. slit sensilla. Each one looks like a tiny crack that transforms as vibrations pass through the spider’s body. (Some evidence suggests that widows can tune into different frequencies. adjust posture.) There is even debate about this because spiders are so good at sensing vibrations. spider or notweb part of the brain.
