Ologies with Alie Ward

Blattodeology (YES, COCKROACHES) with Dominic Evangelista

October 15, 2025

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  • Termites are scientifically classified as eusocial cockroaches, representing a highly organized subgroup within the order Blattodea. 
  • Cockroaches possess defining characteristics such as a leathery egg case (ootheca) and an integral endosymbiotic bacteria (*Blattobacteria*) that allows them to recycle nitrogenous waste (urates) into essential amino acids. 
  • Male cockroaches engage in a unique courtship ritual by offering females a copulatory gift composed exclusively of urine, a behavior likened to a sexual golden shower. 
  • Cockroaches are often misrepresented in media, with the American cockroach being the common subject, while scientists like Dr. Evangelista focus on diverse, often beautiful, and understudied groups like the Neoblatalini from South America. 
  • Cave-dwelling cockroaches, such as the extinct *Simandoa conserfarium* and the bat-riding *Helma Blata Luisrothi*, highlight the extreme diversity and specialized adaptations within Blattodea. 
  • The Madagascar hissing cockroach serves as an excellent ambassador species for outreach because children are generally unafraid of handling them, suggesting that adult aversion to cockroaches is often a learned behavior, not an inherent fear. 

Segments

Cockroach Etymology and Diversity
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(00:03:16)
  • Key Takeaway: The term cockroach derives from Spanish and Latin roots, and the vast majority of the 7,000+ cockroach species live outside human dwellings.
  • Summary: The word cockroach originates from the Spanish cucaracha and the Latin bladda, meaning ’that which shuns the light.’ Over 99% of cockroach species inhabit tropical and subtropical latitudes, such as rainforests, deserts, and temperate ecosystems, and avoid human contact. Only about 10 to 20 species cohabitate with humans.
Termites are Cockroaches
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(00:06:50)
  • Key Takeaway: Molecular phylogenetic studies confirm that termites are not a separate order but are classified as a family of eusocial cockroaches.
  • Summary: Since 2007, termites have been recognized as social cockroaches, sharing a lineage with mantids defined by a perforation in the skull and egg enclosure in an ootheca. Only termites exhibit true eusociality with castes, while other cockroaches display subsocial or solitary behaviors. Some subsocial species maintain small colonies guarded by a matriarch.
Defining Cockroach Anatomy
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(00:09:47)
  • Key Takeaway: Cockroaches are distinguished from their closest relatives, mantises, by their leathery egg case and the presence of endosymbiotic bacteria within their fat cells.
  • Summary: A key feature is the leathery egg case, or ootheca, which females craft with their genitals. They also possess large, pointy cerci on their rear ends that function as sensory organs detecting low vibrations or air gusts. Furthermore, their flat, oval shape is an inherited trait from Carboniferous-era ancestors, optimized for hiding in nooks and crannies.
Locomotion and Size Range
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(00:14:27)
  • Key Takeaway: Cockroaches are naturally fast, agile sprinters whose flat bodies are adapted for rapid evasion, and some forest species can fly for multiple miles.
  • Summary: Cockroaches are optimized for sprinting, using speed and acrobatics to evade predators, which is why field collection often requires bare-handed capture. The smallest species measure about two millimeters, while the largest, like Megaloblatta, have wingspans the size of a hand. Pest cockroaches are generally poor flyers, but forest species can achieve long-distance flight.
Bizarre Mating Rituals
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(00:21:11)
  • Key Takeaway: Cockroach males use their wings during mating to position females while presenting them with a copulatory gift made exclusively of urine (urates).
  • Summary: Males use wings to position females for mating, and the gift they offer is composed entirely of urine, making cockroaches one of the only animals besides humans known to engage in sexual golden showers. This behavior is biologically important because the endosymbiotic bacteria allow cockroaches to recycle these urates into necessary amino acids, effectively reusing metabolic waste as a protein source.
Pest Cockroach Hardiness
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(00:29:39)
  • Key Takeaway: Pest cockroaches are incredibly resilient, capable of surviving weeks without water and months without food, and the American cockroach relies heavily on human habitation.
  • Summary: Pest cockroaches can survive for weeks without water and nearly two months without food, and they can eat nearly anything, including glue or dead skin. The American cockroach is largely dependent on human environments, unlike most other species that thrive in the wild. Pest control recommendations focus on sanitation, closing gaps, and running dehumidifiers, as roaches dry out quickly.
Nomenclature and Odor
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(00:31:38)
  • Key Takeaway: The common names for pest cockroaches are often misnomers, and their characteristic musty odor comes primarily from pheromones, though some species are named ‘skunk roaches’ for their strong smell.
  • Summary: The American cockroach likely originated in Africa, the German cockroach in Southeast Asia, and the Oriental cockroach (Blatta orientalis) is misnamed, originating from the Crimea region. When squished or in high concentrations, they emit a musty smell often described as a mix of BO, mold, or burnt hair, largely due to pheromones.
Parental Care and Reproduction
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(00:54:48)
  • Key Takeaway: Cockroach parental care varies widely, ranging from guarding offspring in burrows to specialized methods like live birth or young piercing the mother’s exoskeleton to drink her blood.
  • Summary: Some subsocial females protect their young in burrows, while termites feed their young wood pulp via butt secretions. Some lineages exhibit internal incubation of the ootheca or true live birth without an egg case. The most extreme example involves young with modified mouthparts that pierce the mother’s exoskeleton to suck her blood, a process Alie Ward notes is akin to nursing but with blood.
Media Portrayals and Study Focus
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(01:00:38)
  • Key Takeaway: The American cockroach dominates media, while scientists are interested in understudied, diverse South American groups like Neoblatalini.
  • Summary: Kafka’s portrayal of a cockroach is mysterious, but generally, cockroaches are not celebrated in media as scientists see them. Dr. Evangelista focuses on the Neoblatalini group from South America, which hasn’t been studied in 50 years and exhibits high diversity and intricate genitalia. Identifying these species is difficult due to outdated 100-year-old literature.
Rare and Cave Cockroaches
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(01:02:12)
  • Key Takeaway: Cave cockroaches like Simandoa conserfarium and bat-riding species illustrate specialized survival strategies and vulnerability.
  • Summary: The Simandoa conserfarium, known from a single bat cave in Guinea, is often cited as an example of a species that went extinct quickly after habitat destruction. This species, however, thrives in captivity and is considered a cute pet with a bumblebee-striped butt and white trim on its pronotum. Another species, Helma Blata Luisrothi, hitches rides on bats to move between caves and is described as stunning, translucent butter yellow.
Overcoming Cockroach Aversion
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(01:03:34)
  • Key Takeaway: Appreciating cockroaches involves recognizing their parental care strategies and observing the beauty of non-pest species.
  • Summary: Dislike for cockroaches is common, but appreciating them can start by recognizing they have some of the best parental care strategies in the animal kingdom. Listeners are encouraged to seek out and photograph forest cockroaches in tropical areas, noting their dazzling colors and intricate patterns, such as the mint green ones or the Lusca Hermetica that glows under black light. Madagascar hissing cockroaches are suggested as good ambassador species because they are calm and easy to handle, unlike faster-moving pest species.
Hissers and Ambassador Species
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(01:06:15)
  • Key Takeaway: Madagascar hissing cockroaches are good ambassador pets, and a white protrusion from a male’s rear may simply be its titillator.
  • Summary: Madagascar hissing cockroaches are generally calm, easy to handle, and interesting to look at, making them good for exposure therapy, though adults often fear them more than children do. When threatened or horny, these roaches produce hissing noises resembling a Windex bottle or duster can. A white, wormy-looking structure coming from a male’s rear end is likely its titillator, or penis.
Fieldwork and Conservation Conflict
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(01:08:16)
  • Key Takeaway: The hardest part of cockroach research is the ethical conflict between conservation goals and the necessity of killing specimens for study.
  • Summary: Dr. Evangelista has conducted fieldwork in South America and West Africa, and also held a postdoc in Paris, which hosts a major collection of cockroach research materials. The most difficult aspect of the job is the need to kill many cockroaches using ethanol to conduct research aimed at conservation. Despite this, the best aspect is their ecological importance, as cockroaches represent a large proportion of animal biomass in tropical rainforest canopies, serving as crucial prey items.
Pest Control and Ecological Role
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(01:11:02)
  • Key Takeaway: While household pests are managed with baits like Advion, cockroaches are ecologically vital, forming the largest proportion of animal biomass in tropical rainforest canopies.
  • Summary: Methods for keeping household cockroaches out include rubbing Irish Spring soap on doorways or using borax baits, with Advion bait being highly reviewed for managing city creatures. Cockroaches are hugely important to certain ecosystems, sometimes constituting the largest proportion of animal biomass in tropical rainforest canopies. Listeners are encouraged to view common roaches as chubbier relatives of praying mantises to foster appreciation.
Aspirational Cockroach Career Advice
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(01:14:08)
  • Key Takeaway: Cockroach tenacity provides aspirational career advice: be willing to ‘scuttle under the door’ and outlast others to achieve goals.
  • Summary: Dr. Evangelista advises that to succeed professionally, one must sometimes cram in through cracks like a cockroach rather than waiting for an open door. This involves sending emails, following up, and being willing to start small, like eating a fingernail on the way to an apple core. The core message is to outlast others, be good to others, keep one’s ‘antenna clean,’ and aggressively pursue opportunities.