“Filthy, absolutely filthy,” Dr. Emily Swanson said while watching a video of a male spider mounting a much larger female and guiding his sexual palpal organ into her epigyne. Under the UV light, their bodies glowed in ghostly colors that made the mating ritual even more bizarre.
As the old joke went, natural selection was about the three Fs: feeding, fighting, and mating. The Giant Zebra spider found in the caves of Mars combined all three in a single romantic session.
In the video, the male spider dug the hairy spikes on his legs into the female’s back. She made a shrill sound that readily excited the male, and he began to writhe and squeeze his organ at her direction.
Dr. Swanson’s focus on the video was such that she didn't notice the silhouette of the man standing in the doorway.
She gasped, and quickly closed her laptop. Then adjusting her spectacles, she said, “my goodness, I did not see you standing there.”
“I didn't mean to startle you,” the man said. “I just took a left turn somewhere and got lost. I’m looking for the neuroscience lab.”
“It’s down the hall to your right,” she said. “Past the cafeteria.”
“Sure thing,” she said and waited for him to leave.
He turned to go but then stopped.
“I know it’s none of my business, but were those Zebra spiders in the video?”
“You’re right, it’s none of your business,” she said matter-of-factly, “but if you’re curious, yes, those were Giant Zebra spiders. I study sexual selection in their species.”
“They kill their mates, don’t they?”
“Oh yes!” she said. “They’re very efficient when it comes to their survival and that of their offspring. In fact, the female mates with several males just to make sure she has plenty of choice.”
"Those bio-engineers do have a sense of humor," he said.
"The behavior evolved naturally," she said correcting him. She opened her laptop. "Close the door, and let me show you."
The man did as she requested and approached her desk. Only the dim light of the laptop screen illuminated the room.
In the video, the male spider copulated vigorously with the female, who made a shrill sound.
“Her cries guide the male behavior,” said Dr. Swanson in her professorial voice. “In this species, males compete with each other for mates. They take the initiative in luring females as in most species, but ultimately, the female spider is the one who decides whose sperm fertilizes her eggs, and she does so by copulating with as many males as possible. The thing is, this behavior was not present in the original lab-grown species but emerged spontaneously after mere decades of evolution. Survival of the fittest in fast-forward. Her choices drive the evolution of her species. My research seeks to understand the mechanisms underlying this behavior. The interplay between male competition for mates and female sexual selection.”
The man remained silent for a moment.
“Truly remarkable,” he said, his eyes glued to the video.
The smaller male spider jumped off the female's back in a burst of seminal fluid.
“Isn’t that neat?” Emily said. “Jumping off like that not only saved his life but also ripped off his sexual organ.”
“Why in the world would the male do that?” said the surprised man.
“To plug her up,” said Emily. “Now she won’t be able to copulate as efficiently with other males. By breaking off his organ, he improves the odds of his sperm being chosen. As far as the female is concerned, she must acquire the best quality sperm she can get to make beautiful babies. So, she’ll mate with many others and choose the best in spite of her condition. It’s like an arms race between the male sperm and the female egg. An evolutionary battle of the sexes.”
“Fascinating,” the man said.
“Yes, I think so. We can learn so much about sexual selection and understand the mechanisms that drive its evolution... even in artificial species.”
The man nodded, then after some brief remarks, he excused himself and left.
Dr. Swanson turned to the screen where another male spider was about to mount the female.
“Oh, you sneaky devil,” she said picking up her pen and notebook.
Later that evening, on the way home, she thought about the man. She didn’t remember any details of his face because it was dark in the lab. Not that such superficial things mattered to her. Or did they? She remembered the way his deep voice made her feel safe, and his scent made her feel warm. Triggers that released some deep rooted instinct.
Really, Emily? Martian spider sex and natural selection? Is that how you plan to attract a mate?
She hadn’t even asked him his name.
She turned on the radio and tried to forget all about males and sexual selection. Riding along the skyway, the sunlight looked beautiful reflected on the lake, so she began to hum along with the tune.
Image by @litguru
This is supposed to be a stand-alone story with a loose over-arching narrative. If you're interested in reading more about the sociobiological adventures of Dr. Emily Swanson, check out the following: