Robert Raven: Why Scientists Study Spiders, Cockroaches and Flies They Fear

Robert Raven does not adore spiders.

They make his flesh creep and bring him out in cold sweats. They have driven him from his tent and kept him awake as they waited on his bedroom wall. When he is particularly exhausted, he sometimes cannot stand even to think about spiders or look at them.

That may seem entirely understandable, yet it is an unexpected stance for Raven. Robert Raven is an arachnologist at the Queensland Museum in Australia, where he has spent more than 40 years handling and investigating these eight-legged sources of fear.

He says the origin of his fear lay with his father, a mining engineer whose work led him into caves draped in cobwebs. His father would set fire to a rolled-up newspaper and - fwoof - burn away the webs. He told his young son that the spiders would tumble from them down the back of his neck.

Raven told ScienceAlert, "The picture of that was quite frightening. And it stuck with me. And I didn't realise that until I started trying to dissect why I was feeling that way. So I thought, all right, you have to learn, you have to face your fear."

"And that's how I got into the spider world."

Scientists fascinated by spiders, cockroaches and flies

The natural world is immense and astonishing, populated by creatures of every kind. Some people are drawn to formidable predators, while others are captivated by the vivid abundance of coral reefs. The attraction of such animals is readily understood by most of us.

Yet certain scientists are devoted to the unattractive and the unpleasant: creatures that tend to provoke fear or revulsion in other people.

For Ed Baker, an entomologist at the University of York and the Natural History Museum in the UK, those creatures are cockroaches. Mention a cockroach and many people picture gloomy, grimy spaces, along with germ-laden feet racing across the kitchen worktop.

Baker arrived at cockroach research indirectly, after studying stick insects. To him, cockroaches belong to a group that has received far too little study and remains poorly understood.

Trilobite roach (Hyposphaeria) family. (felix_riegel/iNaturalist/CC BY-NC)

There are about 4,000 recognised cockroach species, he says. Even conservatively, that represents only around half the true number of species worldwide. Of every known and as-yet-unknown species, just about 40 are pests.

He told ScienceAlert, "We know pretty much all of their biology, they've been used as model organisms, and science for all kinds of things."

"And then you go into the forest somewhere and see a cockroach and there's a good chance it's a new species. Or if it's not, there's a good chance we know absolutely nothing about its ecology. And whenever anyone has the time to start studying a species, you learn so much new stuff - like weird vibrationary behaviours, or mate interactions. There's just so much to know."

Bryan Lessard, an entomologist at Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO), shares that outlook. His work focuses on some especially disliked insects: flies, maggots and mosquitoes.

His route into entomology was also indirect. While studying biotechnology at university, he attended a lecture on forensic entomology, the use of insects to investigate crimes. In particular, it concerned maggots.

(Cory Doctorow/Flickr/CC BY-SA 2.0)

"From then on, I was hooked," Lessard says. During his PhD, he fell in love with flies and went on to build a career researching them. Over the past decade, he has formally described and named 50 species new to science.

"Flies are super biodiverse, with more than 160,000 species known in the world. But the proportion of researchers studying these animals is inverted, with more people interested in studying 'charismatic' vertebrates than flies. That's why we are still discovering hundreds of new species of fly each year."

Fear, disgust and misunderstood animals

At first glance, the aversion we feel towards all three groups appears justified.

Spiders are venomous, which is a sensible reason for caution. Evidence also indicates that their erratic, unpredictable movements frighten us, and that this fear may be innate.

Raven considers the response understandable, although he believes it can be overcome.

He told ScienceAlert, "When you think of the animal as a horrible, intensely frightening organism, then you automatically generate your threatened position."

"If you look at it as we try to get the kids to do - look at those beautiful hairs on the legs, and here's a photograph showing what the hairs look like really close up - they're just so amazing."

The large, beautiful eyes of a jumping spider (Phidippus audax). (Macroscopic Solutions/CC BY-NC)

Flies and cockroaches are both linked in our minds with disease, bacteria and unclean surroundings. Lessard and Baker say that judgement is deeply unfair to the animals.

Baker says, "If there are unsanitary conditions, cockroaches will appear and come in and feed on the unsanitary conditions. So they're associated with unsanitary conditions, but by nature, are not unsanitary."

"If you pick one up, and then you put it down, it will probably clean itself because it thinks the oils from your hand are dirty, and they spend quite a lot of time cleaning their feet and cleaning their antennae, because they're their sensory organs.

"So they're actually pretty clean animals, it's just they're associated with dirt and mess that humans have made. So it's really our fault, not the cockroaches'."

Flies deserve the same reassessment. In our imagination, these insects are often far more revolting than they really are.

(Bryan Lessard, supplied)

Lessard says, "Growing up, I used to think flies were dirty, disgusting and should be exterminated. Jeff Goldblum turning into a mutated fly hasn't helped people fall in love with flies."

"It wasn't until I started learning more about flies that I discovered their importance in the environment. Yes, some species of blowfly can occasionally contaminate our food, but the majority of species do not bug humans."

What stands out about each of these three scientists is that curiosity and fascination displaced their former dislike and misconceptions. More than that, knowledge and understanding appear capable of softening our prejudice against creatures we regard as repulsive.

Baker believes cockroaches can seem more appealing once people discover their similarities to other animals. Some mothers carry their young in pouches beneath their wings, much like marsupials. Others grow horns for contests over mating rights, like deer. One desert species uses its long legs to leap, resembling a desert jumping mouse.

"And there are some species," Baker says, "where the young bite into the membranes and feed off the mother's blood or haemolymph, which is a bit gross, but it's kind of like the start of suckling behaviour."

The vital work of maggots and flies

As Lessard observes, maggots are considerably more useful than they are unpleasant. If these wriggling larvae did not clear away decaying organic waste and return it as nutrients, the world would be much more disgusting. They can assist forensic scientists in estimating the time since a person died, and are highly effective at cleaning septic wounds because they consume only dead tissue.

Flies are pollinators, too.

(Bryan Lessard, supplied)

Lessard told ScienceAlert, "Without flies, we would not have chocolate, since flies are the biggest pollinators of the cocoa plant."

"We are only just discovering how useful flies are as pollinators. Blowflies, the ones that you might see buzzing around your garbage, are fantastic pollinators of native Australian plants. Researchers from the University of New England have shown that blowflies carry twice as much pollen as the European honey bee and are better at pollinating mango and avocado orchards."

Certainly, then, these animals are not as disgusting as they may initially appear. Still, an intense fear of spiders is harder to defeat than simple distaste for blowflies. Raven says that, despite decades as an arachnologist, he has never fully conquered his fear - although some experiences outweigh it.

He enjoys, for example, the challenge of confronting his phobia. He also values talking with people about spiders, listening to their accounts and helping them work through their own fears.

He says, "I love the interaction with people over them, those people teach me about spiders and some of them are very knowledgeable, good eyesight, they see things that I don't see."

"I now have thousands of eyes because of social media. And I hear people's stories, not just about freaky interactions - those are funny - but you hear the most amazing stories about how people dealt with a spider bite. And they just blow your mind."

The mirror spider's (Thwaitesia margaritifera) glorious rear. (hokoonwong/iNaturalist/CC BY-NC)

It can also be astonishing to learn how different spiders behave and move through their surroundings. Raven describes one that sparkles like a disco ball, and another that adds a chemical to its web which imitates female moth pheromones. Male moths arrive seeking a partner, only for the spider to strike them with its web and drag them in.

He is now studying a tiny Australian spider that seeks out leaves containing holes chewed by insects. Concealed behind the leaf, it uses the opening as a trapdoor and waits for an insect to pass. The spider then leaps through the hole.

Reflecting on discovering this hunting technique, Raven says, "I was just transformed. I thought: 'ah, such a wonder'." He may not love spiders, but hearing him talk about them can make it easy to believe otherwise.

"I should be looking at retirement. But I've got so many exciting, different works, documenting these amazing spiders, that I don't want to stop."