The power of cockroach excreta may explain an entomological mystery

The power of cockroach excreta may explain an entomological mystery

Dec 7th 2013 | From the print edition

SMEARING the place you inhabit with faeces is, among people, an act of desperation rarely seen outside the confines of a prison. Some cockroaches, though, do it all the time. Rebeca Rosengaus of Northeastern University, in Boston, thinks she knows why. As she and her colleagues discovered in a study just published in Naturwissenschaften, wood-cockroach faeces protect the insects from a parasitic fungus. This finding, she thinks, may also explain the existence of one of the world’s most successful groups of animals: termites.Wood cockroaches nest in decaying tree trunks, in crevices they plaster with their faeces. These are also home to fungi that parasitise their insect neighbours. Past observations have hinted that cockroach faeces protect against such parasitism. Dr Rosengaus decided to test the idea.

She and her colleagues collected cockroach faeces, mashed them up with water, mixed in fungal spores and smeared the mixture onto slides covered in nutrient-rich agar. As a control, they repeated the process without the faeces.

The fungus germinated on all the control slides. On those smeared with the faecal mix it germinated on only a third. Faeces thus stop fungal germination and presumably protect cockroaches. And what works for individuals might work even better for a huge colony, in which individuals benefit from the pooled excreta of thousands of neighbours. Which is where the termite connection comes in.

Termites, a specialised group of social cockroaches, are one of entomology’s puzzles. Ants, bees and wasps—the other insects that form colonies in which sterile workers raise the offspring of a queen—have unusual genetics. Their workers are female, and these genetics explain the propensity of females to help their mothers reproduce, instead of breeding themselves.

Termites, though, do not have this unusual genetic pattern and the sterile workers come from both sexes. So the question is, what made them become colonial?

Dr Rosengaus speculates that the impetus was faeces-pooling, and she has found that at least one living termite species thought to resemble the earliest members of the group has anti-fungal faeces too. Many a householder has no doubt issued a lavatorial expletive on discovering termite damage to his house. If Dr Rosengaus is correct, such outbursts may be more appropriate than anyone had realised.

About bambooinnovator
Kee Koon Boon (“KB”) is the co-founder and director of HERO Investment Management which provides specialized fund management and investment advisory services to the ARCHEA Asia HERO Innovators Fund (, the only Asian SMID-cap tech-focused fund in the industry. KB is an internationally featured investor rooted in the principles of value investing for over a decade as a fund manager and analyst in the Asian capital markets who started his career at a boutique hedge fund in Singapore where he was with the firm since 2002 and was also part of the core investment committee in significantly outperforming the index in the 10-year-plus-old flagship Asian fund. He was also the portfolio manager for Asia-Pacific equities at Korea’s largest mutual fund company. Prior to setting up the H.E.R.O. Innovators Fund, KB was the Chief Investment Officer & CEO of a Singapore Registered Fund Management Company (RFMC) where he is responsible for listed Asian equity investments. KB had taught accounting at the Singapore Management University (SMU) as a faculty member and also pioneered the 15-week course on Accounting Fraud in Asia as an official module at SMU. KB remains grateful and honored to be invited by Singapore’s financial regulator Monetary Authority of Singapore (MAS) to present to their top management team about implementing a world’s first fact-based forward-looking fraud detection framework to bring about benefits for the capital markets in Singapore and for the public and investment community. KB also served the community in sharing his insights in writing articles about value investing and corporate governance in the media that include Business Times, Straits Times, Jakarta Post, Manual of Ideas, Investopedia, TedXWallStreet. He had also presented in top investment, banking and finance conferences in America, Italy, Sydney, Cape Town, HK, China. He has trained CEOs, entrepreneurs, CFOs, management executives in business strategy & business model innovation in Singapore, HK and China.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: