A rare cockroach expert who names new species after Tolkien's fictional creatures, Philippines scientist Christian Lucanas says the disease-bearing bugs deserve more study – and credit – for the crucial role they play in preserving the planet's ecosystem.
Issued on: 08/03/2026 -
Cristian Lucanas, an entomologist from the University of the Philippines Los Banos, shows preserved specimens of cockroaches. © Ted Aljibe, AFPA thin band of light from Cristian Lucanas's headlamp pierces the blackness of a Philippine rainforest as he digs through the underbrush before gently scooping up a cockroach with his bare hands.
As the Southeast Asian country's lone expert on the oft-misunderstood insect – and discoverer of 15 species – friends have dubbed the soft-spoken scientist "Ipis Lord", after the local name for the ubiquitous bug.
While fully aware most view cockroaches as disgusting, disease-bearing pests, the 31-year-old University of the Philippines entomologist says they deserve more study – and credit – for their key role in the planet's ecosystem.
"I also hated cockroaches when I was a child," Lucanas said with a grin during an interview with AFP in the college town of Los Banos, south of Manila.
"Fear of cockroaches is innate," he conceded, adding he usually tells people "I work in a museum" when asked about his job.
READ MOREThe Bright Side: Humble bugs are popular pets in nature-loving Japan
His girlfriend, also an entomologist, is more understanding, though her work focuses on insects less reviled than the cockroach, of which there are more than 4,600 known species.
"It's possible the real total is double or even triple that," said Lucanas, unable to hide his enthusiasm.
"For the longest time, no one was studying them," he said, calling it "sad" given the size and variety of the archipelago nation's cockroach population.
The massively biodiverse Philippines has about 130 known species, three-fourths of which are found nowhere else on earth.
Lucanas thinks there could be another 200 local varieties yet to be documented.
"Because of their outsized role in the ecosystem, its processes would be hampered if they disappear," he said.
Like dung beetles and earthworms, cockroaches are detritivores, built to eat and break down dead organic matter – including their own kind – and return them to the soil.
While some cockroach species do carry disease-spreading microbes, a world without them would slow the process of decomposition crucial for sustaining ecosystems, he said.
WATCH MOREBiologist Dave Goulson on the magic of insects and their crucial role on our planet
Birds and spiders would lose a key food source, and plants would absorb less carbon dioxide, potentially contributing to global warming.
Even so, Lucanas keeps a can of bug spray handy at work, ready to kill any live cockroaches that might view the museum's 250,000 preserved insect species as a potential snack.
Lucanas's obsession began 12 years ago on a field trip to a bat cave on a remote island, its floor crawling with cockroaches feasting on guano.
When his biology class adviser was unable to identify the species, Lucanas knew he had found his niche.
A lifelong fan of J.R.R. Tolkien, Lucanas often names his discoveries after creatures in the author's "Lord of the Rings" trilogy: "Valar", "Hobbitoblatta", and "Nazgul".
Their ranks are set to grow once he finishes writing up scientific papers on his newest finds, he promised.
Given the uniqueness of his specialty, the young scientist occasionally finds himself in demand, albeit for very specific situations.
The country's biggest bug spray firm once invited him to lecture its staff on cockroach identification.
Its top restaurant chain also sought his advice, desperate to stop raids on their commissary by so-called German cockroaches, an invasive species from India.
"Control is not really my forte," Lucanas admitted.
But cockroaches are far from the indestructible creatures that they are often portrayed as, he insists.
It is not true, for instance, that cockroaches will inherit the earth after a nuclear war, he said, noting that their resistance to radioactive exposure is about on par with other insects.
Humans, not bombs, pose a more immediate threat to the creatures, he said, noting that some species, especially in mountain environments, reproduce slowly and could disappear if their habitats are encroached upon.
Several cave-dwelling Philippine species first described in the 1890s during the Spanish colonial period "have not been seen again" since their habitats were opened to tourism, he explained.
He laments that most science funding in his country "goes to research that will directly affect humans", worrying that at best he will only be able to catalog and explain the Philippines' cockroaches.
But for now, that's enough, he said when asked about the decades still left in his career.
"I think I'll stick with what I'm doing. It's how I've built my reputation.
"And I really do enjoy working with cockroaches."
From pest to plastic fighter: Cockroach metabolism unlocks rapid polystyrene degradation
image:
Integrated host–microbiome network driving polystyrene degradation in Blaptica dubia
view moreCredit: Environmental Science and Ecotechnology
Plastic pollution remains one of the most persistent environmental crises, with polystyrene (PS) among the hardest polymers to break down due to its stable aromatic backbone. A new study demonstrates that the cockroach Blaptica dubia can efficiently biodegrade polystyrene through a tightly integrated gut microbe–host metabolic system. The insects removed nearly 55% of ingested polystyrene within 42 days, achieving a degradation rate far exceeding those reported for other plastic-feeding insects. Analyses of residual polymer in frass versus original PS confirmed depolymerization, oxidation, enrichment of stable isotope 13C and partial mineralization. By coupling microbial enzymatic cleavage with host β-oxidation and tricarboxylic acid cycle pathways, the cockroach transforms plastic-derived carbon into metabolic energy, revealing a powerful biological strategy for tackling recalcitrant synthetic polymers.
Global plastic production now exceeds 400 million tons annually, and PS remains one of the most widely used yet environmentally persistent polymers because of its aromatic backbone and chemically stable carbon–carbon bonds. Once fragmented into microplastics, PS can accumulate in soils and aquatic systems as well atmosphere, adsorb pollutants, and enter food webs. Although several insect species, such as mealworms and greater wax moth larvae, have shown partial biodegradation capacity, their degradation rates remain modest, and the metabolic fate of breakdown intermediates is poorly resolved. Most previous studies focused primarily on gut microbes or depolymerization alone. In light of these challenges, a deeper investigation into coordinated host–microbiome metabolic mechanisms is urgently needed.
Researchers from Harbin Institute of Technology with collaborators at Stanford University reported the findings (DOI: 10.1016/j.ese.2026.100679) on February 25, 2026, in Environmental Science and Ecotechnology. The team investigated the biodegradation capacity of the cockroach Blaptica dubia, integrating metagenomics, transcriptomics, 13C isotope signature, and polymer chemistry analyses. Their results reveal a coordinated microbe–enzyme–host metabolic network that enables rapid depolymerization, biodegradation of daughter intermediates, and metabolic assimilation of polystyrene microplastics, offering new insight into how insects may adapt to synthetic carbon sources in the Anthropocene.
In controlled feeding experiments, cockroaches consumed an average of 6.0 mg of polystyrene per individual per day. Over 42 days, they removed 54.9% of ingested plastic, corresponding to a specific degradation rate of 3.3 mg per cockroach per day—an order of magnitude higher than rates reported in mealworms, superworms and other plastic-degrading insects. Gel permeation chromatography revealed significant polymer breakdown, with number-average molecular weight decreasing by 46.4%. Stable carbon isotope analysis showed enrichment of δ¹³C in residual plastic, confirming preferential metabolic utilization of lighter carbon isotopes which is strong indication of biological reactions. FTIR, NMR, thermogravimetric, and Py-GC/MS analyses detected newly formed oxygen-containing functional groups, demonstrating oxidative chain scission and aromatic ring modification.
Metagenomic sequencing revealed that polystyrene feeding reshaped the gut microbiome toward plastic-degrading taxa such as Pseudomonas, Citrobacter, Klebsiella, and Stenotrophomonas, accompanied by enrichment of oxidoreductases and transferases. Network analysis showed tightly connected microbe–enzyme modules driving aromatic oxidation. Meanwhile, host transcriptomics revealed strong upregulation of β-oxidation, NADH dehydrogenase, oxidative phosphorylation, and TCA cycle pathways, indicating that microbial degradation intermediates were absorbed and metabolically integrated. Together, these findings outline a synergistic cascade: microbial oxidative depolymerization followed by host energy assimilation.
“This work demonstrates that plastic degradation in insects is not merely a microbial phenomenon, but a fully integrated metabolic collaboration,” said the study's corresponding author. “The cockroach does not simply fragment polystyrene—it metabolically processes the breakdown products through its own energy pathways. The coupling of microbial oxidation with host β-oxidation and the TCA cycle represents a systemic adaptation to synthetic carbon sources.” The researchers emphasize that this tripartite host–microbe–enzyme cooperation explains the unusually high degradation efficiency observed.
The discovery expands the biological toolkit available for addressing plastic pollution. Rather than relying solely on isolated enzymes or engineered microbes, future strategies may draw inspiration from integrated host–microbiome systems capable of both depolymerization and carbon reutilization. Although direct environmental release of cockroaches that includes more than 4,400 species around the world is not currently practical or advisable, decoding their metabolic networks could inform synthetic biology approaches, microbial consortia design, or enzyme engineering platforms for plastic waste valorization. More broadly, the findings suggest that insects may possess unexpected evolutionary flexibility to adapt to anthropogenic polymers, offering a new paradigm for sustainable bioremediation in a plastic-dominated world.
###
References
DOI
Original Source URL
https://doi.org/10.1016/j.ese.2026.100679
Funding information
The authors gratefully acknowledge the Science Foundation of the National Engineering Research Center for Safe Disposal and Resources Recovery of Sludge (Harbin Institute of Technology) (No. K2024A007), the National Natural Science Foundation of China (Grant No. 52170131), and the State Key Laboratory of Urban-rural Water Resource and Environment (Harbin Institute of Technology) (No. 2025TS44).
About Environmental Science and Ecotechnology
Environmental Science and Ecotechnology (ISSN 2666-4984) is an international, peer-reviewed, and open-access journal published by Elsevier. The journal publishes significant views and research across the full spectrum of ecology and environmental sciences, such as climate change, sustainability, biodiversity conservation, environment & health, green catalysis/processing for pollution control, and AI-driven environmental engineering. The latest impact factor of ESE is 14.3, according to the Journal Citation ReportsTM 2024.
Journal
Environmental Science and Ecotechnology
Subject of Research
Not applicable
Article Title
Host metabolic integration enables superior polystyrene degradation in cockroaches
