Comics often have details and sophisticated allusions that could and should be leveraged in various ways, including in the classroom, to arouse the interests and hold the attention of students (Rama and Vergueiro 2004; Marchiori 2011; Quartim 2013; Miranda 2014).

Despite being a creatively free process, the composition of a comic book character often has interesting ‘real-life’ influences. Given the strong connection between arachnids (especially spiders, scorpions and mites, all belonging to the class Arachnida) and human beings (Mundkur 1983; Cloudsley Thomson 1990, 2001; Monzón and Blasco Gil 1995, 1996a, b, c, d, 1997, 1998; Ruppert and Barnes 1996; Melic 1997, 2002, 2003), it is not surprising that they have inspired many fictional characters.

Focusing only on the two major American comics publishers, DC Comics and Marvel Comics, we conducted an inventory of the characters that have been inspired by arachnids in some way. We have compared the features of these characters with the morphology, biology and behaviour of living arachnids from the ‘real’ world.

For the inventory of characters, we used basic sources like encyclopaedias (Beatty et al. 2009; DeFalco et al. 2009; Saunders et al. 2010; David and Greenberger 2010; Beatty et al. 2012), available comics and websites. We classified the characters according to the publisher, social role (hero or villain), taxonomic classification (order) of the inspiring arachnid, the presence/absence of features associated with arachnids, and the decade of creation. We also considered the “femme fatale” effect, something the general public in general observe in spiders, derived from the fact that some female spiders devour their partners after copulation (Thorp and Woodson 1976; Foelix 2011).

The classes were statistically compared through the Pearson’s nonparametric chi-squared test (Siegel 1981), and the results were considered significant with “p” values less than 0.05, always comparing one by one (1 degree of freedom).

Issues relating Zoology to cultural events have been gaining prominence recently. Coelho (2000, 2004) studied insect references in the lyrics and cover art of rock music albums, respectively. Ashenden (2000–2001) made an entomological survey of the renowned novel Ada, by Vladimir Nabokov. Cherry (2002, 2005) studied the role of insects in mythology and magic, respectively.

Mariño Pérez and Mendoza Almeralla (2006) made a critical analysis of the presence of insects and other arthropods in films from 1938 to 2002. Costa Neto (2006) surveyed the use of insects in popular customs and celebrations in northeastern Brazil. Mendonça (2008) studied folkloric demonstrations that could enhance the learning of Zoology at school. Chantoury-Lacombe (2009) studied the connection between insects and painting techniques used in renaissance Europe. Monserrat (2009, 2011) approached the presence of arthropods in paintings of Hieronymus Bosch and Salvador Dali, respectively. Carvalho (2010) investigated the symbolic meaning of two butterfly species represented in paintings of the XV century. Monserrat (2010) made a study of tattoos containing visual references to arthropods. Nemésio et al. (2013) approached the use of different taxonomic groups of animals in postage stamps. Recently, animal species have been named after pop culture icons, such as artists (Dumas et al. 2013), athletes (Santos and Nessimian 2009) and fictional characters. Of the latter, interesting examples include a leafhopper (insect) named after Batman (Rodrigues et al. 2012) and a shrew (mammal) named after the god Thor (Stanley et al. 2013).

Through history, arachnid symbolism in culture and mythology has been remarkable. The cultural entomology of the Sumerian era (3,500 B.C.), for example, is fundamentally based on arachnids. The most important arthropods in this mythology are scorpions and spiders (Melic 2002). Astronomers of Babylon were the first to recognize the Tauro and Scorpion constellations around 4,000 years ago, showing the influence of these animals on that people (Melic 2003). In Navajo Creation myth, Grandmother Spider Woman spins all life from the shimmering threads in her belly (Bartlett 2009). The ancient Vedic philosophy of India suggests that a spider wove the veil of illusion, which hides the supreme reality. In western Africa, Anansi, the spider, prepared the material of which the first human beings were made, and so created sin, the moon and the stars (Cicchetti 2003). Old assertions concerning the birth of the scorpion emerging from various corpses are interpreted as probably resulting from observations of scorpions preying on arthropods on carcasses. Some ancient Egyptian myths emphasize the sacred character of the scorpion as the protector of marriage, and this curious veneration results from accurate observations of scorpions’ sexual behaviour and courtship (Ferrer 2009). In pop culture, spiders have been highlighted in epic literary sagas (and consequently in the movies), such as Harry Potter and the Chamber of Secrets (2003) and The Lord of the Rings - The Return of the King (2004). The spider generally symbolizes patience and tenacity, due to its hunting skills. In addition, it has a lugubrious side that fascinates and scares, enhanced by its poison, which causes paralysis and death to its victims.

In the Roman poet Ovid’s collection of stories about the rivalry between gods and mortals, Arachne was a beautiful girl highly skilled in weaving who was once challenged by Athene (Minerva), goddess of the wisdom, weaving, and strategy, to a contest. Arachne wove a tapestry of marvelous beauty on which she depicted the amours of the gods and goddesses. The beauty and the subject of the tapestry so enraged the goddess that she ripped Arachne’s work into shreds. Arachne, overcome with despair, hung herself. Mercifully, Athene gives her life back turning her into a spider and cursing her and her descendants to weave for all time (Thorp and Woodson 1976; Fantham 2004).

Arachnids are zoologically placed in the class Arachnida, a group that contains 114,275 species described so far, distributed among 11 extant orders (Zhang 2013). They are part of the subphylum Chelicerata, one of the largest of the phylum Arthropoda (Zhang 2013). The class includes many common and familiar forms, such as spiders, scorpions, and mites (Ruppert and Barnes 1996; Brusca and Brusca, 2003; Zhang 2013).

The main morphological characteristics of Arachnida are the division of the body into two parts, the prosoma (or cephalothorax) and the opisthosoma (or abdomen), the presence of chelicerae (the mouth part of the arachnids, also called fang), and the presence of eight legs (Figure 1A, B). The fangs of all arachnids lacerate their prey, and spiders have venom glands (Figure 1B). Scorpions also have venom glands, but they are present in the last segment of the metasoma (Figure 1A) that also helps immobilize and digest their prey. All arachnids are easy to recognize because of their body divisions and their eight legs, but the Acari (mites and ticks) have great diversity of shape, and most of them have the prosoma and the opistosoma fused, so both parts are not distinguishable; in these animals just the legs and the mouth parts are recognizable as joint parts (Figure 1C). In the spiders one appendage is greatly responsible for its enormous diversity, the spinnerets (Figure 1B), which are associated with glands that produce the silk they use to build their webs.

We ranked Marvel and DC characters according to arachnid features, such as web weaving (only in spiders), venom inoculation (in both spiders and scorpions), exoskeleton (responsible for surface resistance and hardness, among other advantages, in all arthropods), multiple eyes (allowing some arachnids to form images and others to differentiate light from dark), chelicerae, eight legs, a post abdomen (for example, the scorpion’s metasoma, popularly called its “tail”) and the ability to climb vertical smooth surfaces (in spiders and mites).

We recorded 84 Marvel characters (Table 1; Figure 2) and 40 DC characters (Table 2; Figure 3). Most of the characters (75, almost two thirds of the total) have been created since the 1990s (Table 3). The chi-squared test results are summarized in Table 4. As a probable consequence of Spider-Man’s success as a pop culture icon, Marvel has significantly more arachnid characters than DC. Arachnids account for about 1.68% of Marvel’s 5,000 or so characters created so far (Marvel 2014). On the other hand, of DC’s cast of over 10,000 characters (DC 2014), arachnid-inspired characters represent only 0.40%. If we merge the two publishers, the arachnid-inspired characters comprise approximately 0.83% of the total.

As for taxonomic classification, the characters were based mostly on the order Araneae (82.93% in DC, 84.71% in Marvel, 81.13% for both publishers). Of the total characters, 80.65% are human (85.00% in DC, 77.38%, in Marvel). The majority of the Araneae-derived characters are human beings with specific arachnid features (74.19%) rather than simply being named after spiders. Marvel characters (88.10%) have more arachnid features than DC characters, where there is no significant difference between characters with or without arachnid features.

Villains (60.91% of total) are significantly more numerous, considering the sum of the two publishers. Arachnids have bad reputation for being dangerous (Thorp and Woodson 1976; Ruppert and Barnes 1996). Since the public usually considers spiders, scorpions and mites “harmful” in general, we expected a larger contingent of villains because the general public usually considers spiders, scorpions and mites “harmful”. However, analysing the two publishers alone, we have a very interesting difference. In DC, the pattern was maintained, with significantly higher number of villains. Nevertheless, there was no statistical difference between the amount of villains and heroes in Marvel characters. It did not happen probably due to a certain friendly neighbourhood character…

In 1962, one of the most popular Marvel titles, Amazing Fantasy, was going downhill, with disappointing sales. With the risk of the series being cancelled, editor and writer Stan Lee presented executives a new and completely different character: a comics character superior to everything that anyone had seen up to that time. This character had problems inherent to youth, such as relationship difficulties, school problems, and lack of economic stability (David and Greenberger 2010). At the moment Peter Parker gets his powers from the bite of a mutant spider, he thinks immediately about taking personal advantage of it, as any normal human being would. In other words, Stan Lee offered a human character who behaved like an ordinary person. Only after experiencing a personal tragedy, exhaustively explored in different media (the murder of his uncle who raised him), the new character learned his lesson, and forged one of the most famous quotations of pop culture, “with great power comes great responsibility”. When the combined artistry of Jack Kirby and Steve Ditko forged the cover of Amazing Fantasy # 15 in August 1962 (Lee and Ditko 1962), the world gained one of its modern icons. Spider-Man and his alter ego Peter Parker became well-known in the four corners of the earth. The audience identified with that character, who was powerful and heroic, but at the same time full of everyday problems, and he certainly changed the way the world of comics would see spiders and related creatures from that day on. Marvel, then, became the publisher of arachnids.

Although arachnid comics characters form a large group in absolute terms (over a hundred characters), very few have recognized standing, and they are concentrated at Marvel. Besides the aforementioned Spider-Man, his incarnations in alternate realities and parallel universes, and the villains he faces (such as Venom, Carnage, Tarantula and Scorpion), only the Black Widow is well-known by non-comic book fans. This is certainly due to the recent releases of the Marvel movies.

Like Spider-Man, the Black Widow also has human features that may have leveraged the character for success. After the supposed death of her husband, a test pilot, Natasha Romanoff (or Natalia Romanova), enlisted in the Soviet spy agency, the KGB. A superbly trained athlete, Romanoff brilliantly learned the arts of espionage, earning the honorific code name Black Widow. Later on, she was co-opted by S.H.I.E.L.D. (Strategic Homeland Intervention, Enforcement, and Logistics Division), an agency linked to the U.S. government. A character created by Stan Lee and Don Heck, the Black Widow had its debut in Tales of Suspense #52 in April 1964 (Lee and Heck 1964; DeFalco et al. 2009). Despite eventually playing important roles in some sagas in the Marvel Universe, usually related to espionage and the Cold War, the super-agent of KGB and S.H.I.E.L.D. only exploded in popularity with Scarlett Johansson’s performance of the character in the blockbuster film The Avengers (2012), directed by Joss Whedon. The film is one of the most profitable in the history of the movies, having risen more than U$ 1 billion at the box office.

Although not endowed with superpowers, the Black Widow is well-respected by her colleagues and opponents. Among her most striking qualities are agility, attractiveness, the ability of an escape artist, intellect, leadership, marksmanship, stamina, stealth, unarmed combat ability and weapon mastery. Interestingly enough, those who meet the character do not immediately realize her connection with spiders. But the code name itself which consecrated her among comics fans alludes to a group of spiders, the black widows (genus Latrodectus Walckenaer, 1805; Family Theridiidae), who are often presented as “femmes fatale”, reminding readers of the mating ritual in which the female often devours the male (Thorp and Woodson 1976; Ruppert and Barnes 1996). As an additional curiosity, the average viewer of The Avengers may not associate Scarlett Johansson’s character with arachnids, but cinephiles may remember the actress from the film Eight Legged Freaks (2002), directed by Ellory Elkayem.

The order Araneae (spiders) has inspired the overwhelming majority of comics characters (over 80%). Some features and behaviours of these characters refer, in fact, to real spiders. In urban areas, for example, it is common to have small spiders (mainly of the family Pholcidae) that inhabit human residences; these spiders weave webs in corners where the walls and ceiling meet. Jumping spiders (Family Saltidae) are also common, as are wandering spiders that expertly roam over vertical surfaces and, occasionally, hang by silk threads. These behaviours (climbing walls and moving around using silk threads) are common in many of the comics characters based on spiders. Virtually all the characters derived from Spider-Man (besides, of course, himself) present such modes behaviour.

Other characters, especially women, use some power of fascination and seduction to fight their rivals. These are the “femmes fatale”, whose inspiration must have been the complex mating rituals of spiders. Finally, lethality is a registered trademark of many characters. Some are efficient killers, using weapons or poisonous gadgets to beat their enemies, which must have been inspired by the efficiency of spiders as notorious hunters, injecting paralyzing venom into their prey through the chelicerae.

About 15% of the characters have some inspiration in arachnids of the Order Scorpiones (scorpions). Many of these have typical features of the creatures that inspire them, such as some sort of tail (alluding to the metasoma, the second part of the abdomen of a real scorpion; Figure 1A) and use of some kind of poison. Many are called “Scorpion,” and McDonald Gargan is the most famous of them because he is one of the main villains of Spider-Man.

The number of characters inspired by the order Acari (which includes mites and ticks) is unrepresentative (about 4%) of the total. The arachnid features of this Order in characters are tenuous. There are four characters named, jokingly, after the term “mite” (Bat-Mite, Dan the Dyna-Mite, Dyna-Mite and Dyno-Mite Dan). Of these, only the first has features typically associated with group members such as ticks, being small and sticky. A hardcore Batman fan, this character often puts his idol in trouble.