There’s so much more to Penn State Behrend’s faculty and staff members than what you see them doing on campus. In this occasional series, we take a look at some of the interesting, unconventional, and inspiring things that members of our Behrend community do in their free time.
By Heather Cass
Publications Manager, Office of Strategic Communications, Penn State Behrend
Two of the most frightening things known to humans – advanced math and tarantulas – are some of Dr. Dan Galiffa’s favorite things. The associate professor of mathematics owns thirteen tarantulas and says the highly venomous spiders make great pets.
“They are one of cleanest and most fascinating animals,” Galiffa said, as his Honduran curlyhair “Curly” (Tliltocatl albopilosus), a thirteen-year-old tarantula about the size of his palm, slowly walks over and around his hand. “Each spider has a unique personality.”
Rosalinda, a Chilean rose, was his first tarantula. Galiffa acquired her eight years ago and liked her so much that he has since gathered twelve more tarantulas, for a total of thirteen spiders of twelve different species, including greenbottle blue, Venezuelan sun tiger, Costa Rican zebra, Chilean copper, Mexican red knee, Arizona blonde, Brazilian salmon pink, Columbian giant red leg, and Mexican red rump.
One of his most beautiful and exotic is Blue, a cobalt blue tarantula native to Myanmar and Thailand. As with most things in nature, the vibrant color is a warning.
“They’re high venomous, extremely fast-moving, and one of the most defensive species of tarantula,” he said. “Many people who own them don’t handle them.”
Galiffa does and said she is a calm and “sweet” spider. That said, he is always respectful of the spider’s space and temperament. No stranger to deep research, Galiffa has done his homework.
“I spend a lot of time learning about them, reading whatever I can find, including some scientific articles and papers that can be pretty specific,” he said. “But I actually did a lot of my mathematical research work in epidemiology, so I’m familiar with the biological science.”
There is much work to do in tarantula taxonomy. “Scientists are still learning a lot of basic things about them,” he said. “The classifications are still not solid.” He estimates there are more than 1,000 species of tarantulas and new discoveries lead to changes in taxonomy. “There are about 45,000 known spider species, in general,” he said.
We talked with Galiffa and Curly (though she was pretty quiet) to learn more about tarantulas and how they can sometimes serve as teaching aids.
What types of courses do you teach at Behrend?
The entire calculus sequence, differential equations, linear algebra, and other advanced math classes.
What is appealing to you about tarantulas?
They make really great pets. They are clean, quiet, easy to care for and they all have their own personalities. It is an exciting challenge to try and understand a species that is so far removed from humans. They communicate with their actions and behaviors.
Why do you think people are so afraid of spiders?
I think spiders get a bad rap. Anytime someone has an odd welt, and it has a visible hole, they call it a spider bite. I always ask the question, “Did you see the spider bite you?” I’ve never had anyone say yes. More than likely, the injury was inflicted by a different insect. Spiders rarely bite unless they are directly threatened.
Where did you get your tarantulas?
I bought them at pet stores, online, and at exotic animal expos. A couple of them are rescues from people couldn’t care for them anymore.
What do they eat?
Worms, crickets, roaches. Basically, they eat anything alive that is smaller than they are. They only eat a few times a month.
You handle all of your tarantulas. Does each species feel different?
Oh, yes. The bristles can be soft, hard, very long, short, thick, or thin. Additionally, some tarantulas are much faster than others. Blue’s speed would blow you away. She could be on the other side of my office in seconds. The same is true of the Sun Tiger.
Are they venomous?
Yes, every one of them is venomous, but they are not aggressive. The venom is not all bad. It is used in some medicines, and it’s not lethal to humans.
What would happen if you got bit?
I have held my tarantulas thousands of times and have never been bitten. If someone were to get bitten, it would probably because they were careless in handling the spider. In any event, there are two types of bites, dry and wet. A dry bite is a puncture wound from fangs. A wet bite is when the tarantula actually uses their venom. They rarely do that. They don’t even use venom when catching their prey unless it is absolutely necessary. A dry bite would be handled like any normal puncture wound with some antibiotic cream and a bandage. A wet bite should probably be seen by a doctor but, again, it’s rare and the venom is not lethal.
How long do they live?
Twenty to forty years with females living longer than males. I have eleven females and two males. When the males mature, they seek out females for mating and will die shortly after, so if a keeper has a male, it’s best to send him to a breeder after he matures. I will have to do this with both of my males, and I’ll be very sad when that time comes. By the way, females can produce egg sacs with over 1,000 eggs!
You’ve used your tarantulas as teaching aids before in Behrend’s K-12 outreach programs. What do you teach with them?
There are many things we can teach with spiders – web strength and construction, genetics, population dynamics, gait analysis, and blood flow, which is quite fascinating in tarantulas since their blood flows through their entire body. They don’t have veins like humans do.
How can you use them to teach math modeling?
We can model them as predators and as prey. We can also study the genetic probability of obtaining certain variations of a given species using probabilistic models. For example, there are three forms of Chilean rose tarantulas – the gray, red, and pink color forms. My spider, Rosalinda, is gray form and Charlotte is a red form. The students in my workshops do a basic version of this very type of modeling and then get to see the differences in the color forms in my actual tarantulas.
Do you have any other pets?
I also have Madagascar hissing cockroaches and a skinny pig (hairless guinea pig) named Hamilton. I previously had two skinny pigs—Perry and Ty—who played games and did tricks.
What do you want people know about tarantulas beyond what we have covered above?
Here are some interesting facts:
- Tarantulas do have eight eyes, but scientists are not sure how well they see.
- Tarantulas have bristles, not hair. Only mammals have hair. The bristles give them a lot of information. So, yes, “spider senses” are a real thing, not just something made up for the Spider-Man comics.
- Tarantulas use their senses to assess everything that’s happening around them and they have amazing perception despite the fact that they cannot smell and have no ears.
- At the end of each of the tarantulas eight legs are two retractable claws, similar to those in a cat. They use these for mobility.
- In addition to their eight legs, they possess two pedipalps or additional appendages that are located at the front of their bodies.
- Since tarantulas are arthropods, they have to molt in order to grow. When a tarantula molts, it can often change color and grow exceedingly large.
- Tarantulas can spin webs. The webs are not like commonly seen ones used to catch prey but are used to line their burrows and keep them safe, for example, spinning a trip “wire” near their home to sense prey and potential predators.
- Tarantulas are opportunistic predators, which means they wait for the prey to come near their home, then attack it with extreme speed and accuracy.
- Tarantulas have a wide variety of coloration and patterns. They are quite stunning when viewed in the right light.