This week, we want to highlight the work of one of the Center’s affiliates, Dr. Nate Morehouse.
Dr. Morehouse leads a lab that studies insects and spiders. He has a special interest in how they see the world, and how their vision influences the choices they make. He was drawn to the University of Cincinnati because the school has a strong community working on the biology of vision, philosophy of perception, and other fields related to sight. He is currently part of an effort to create a central place for this community through the Institute for Research In Sensing (IRIS). Planning is ongoing, but programming is staged to begin by Spring 2021.
Dr. Morehouse is partly interested in the vision of spiders and insects because of the diversity of ways that their eyes function. Vertebrates all have eyes similar to a camera; they have a single lens in front of a cavity above a sheet of cells that receives light. Arthropods have a wider diversity of types of eyes. In insects, the most common is the compound eye, which has thousands of individual flat lenses that are all sensitive to light. The information from these pieces together a clearer mosaic image. They also have a lens that gives them separate information about which way is up and helps them make quick decisions important to flight. Spiders are even more complex; they have 8 eyes. 6 of these evolved from compound eyes, derived from a common ancestor with insects. However, these have lost their ability to create a detailed image, likely because spiders lived underground for a large part of their evolutionary history. These eyes have a very low resolution and cannot see color, much like our peripheral vision. Their other eyes collect information for a more complex color image. They form at a different stage in the spider’s development, and even connect to a different part of their brains. This pair of eyes has a single lens, with a long cavity behind it, like a Galilean telescope. This is called a diverging lens, and magnifies anything they focus on. This means that despite having eyes that are only ½ mm wide, they can see patterns as well as an elephant can and can see better than most other animals their size.
One of the overarching questions Dr. Morehouse and his lab are pursuing is “why?” Spiders have 3-color, vision like humans do, although the exact colors they see are different. Some can see even more than 3 colors. Their interactions, especially during mating, are very reliant on visual cues and color. However, it is unlikely that these displays evolved until after their vision did; after all, why show off if no one can see it? So why did they evolve such complicated vision in the first place? To help them hunt? To avoid something toxic? This research has taken them around the world.
Ongoing research in the lab includes whether the male and female audacious jumping spiders see the world differently. Both sexes track each other’s movements closely during mating and develop in similar ways. One notable difference is that the females have an extra stage or two of development (instars) before maturity, which might allow their eyes to get bigger. There are some differences in the way genes linked to vision are expressed, but the physical effects of that expression are still being figured out. Dr. Morehouse also has students working on the evolution of illusions and how non-human animals discriminate faces. Such studies are possible with arthropods because the lab has technology that can track the movement of their eyes.
Dr. Morehouse was inspired to study arthropods when he was three years old; he would go into his backyard and pick up bumblebees, get stung, and pick them back up. He tries to foster the curiosity of children through long term mentoring programs. He participates in the STEM Girls programs at the Cincinnati Museum Center, afterschool programs, and summer camps. Most recently, he ran a summer camp that allowed students to write their own superhero persona, including a disguise, personality, and power, that was inspired by the natural world. At the end of the week, he showed up in disguise as a supervillian with his own powers, and challenged them to defeat him with their own creativity.
Dr. Morehouse continues to be excited about his field. It has incredible implications for technology; understanding how animals process information could inspire biomedical advances, the engineering of computers that can process information as quickly as arthropods, and programming for the decision making of autonomous cars. In his words, “the natural world has had millions of years to figure out the answers to questions that we are only beginning to ask.” But Dr. Morehouse’s main mission is more philosophical.
“To be honest, those [questions] aren’t what motivate me. Its cool, but it doesn’t drive me. I would feel like my life had been wasted if I didn’t spend it in the pursuit of curiosity. …I actually think that to be curious is an essential part of what it means to be human. If we forget …it as a basic human pursuit, we’re lost. We should encourage healthy curiosity. In part, what I’m doing is art: I want to spark the curiosity of others. Have I changed how people view their world? Is there more magic to their backyard? If I can just move people’s feet from where they were before, that’s success.”
To read more about on-going research in the Morehouse lab, click here.