Parasitic worms 'manipulate' mantises onto asphalt roads, say researchers
Parasitic worms that alter mantis behavior to seek horizontally polarized light—leading them onto asphalt roads instead of water—prompt broader reflections on how parasites and microbes can manipulate host behavior to complete their life cycles. Commenters connect this to known human-affecting organisms like Guinea worm, rabies, and Toxoplasma, as well as to gut microbiome research suggesting microbes may influence cravings and mood. The exchange raises deeper questions about how much of what we call “human nature,” including religion, risk-taking, and even political views, might be subtly shaped by biological or memetic “parasites.”
Behavior-Manipulating Parasites and Pathogens
- Multiple examples discussed: Guinea worm, toxoplasma, rabies, horsehair worms, cordyceps, lancet liver fluke.
- Concern that strong behavior-altering parasites in humans would be detected and eliminated; subtle effects (e.g., suggested increased affection toward cats from toxoplasma) seen as more plausible.
- Some imagine hypothetical STDs that increase promiscuity; commenters note current STIs mainly cause unpleasant, discouraging symptoms.
Human Parasites and Public Health Responses
- Guinea worm lifecycle and eradication efforts described in detail, including behavioral manipulation (forcing people into water via painful blisters).
- Intervention “hacks” the lifecycle by using closed water containers so emerging worms release larvae into disposable water instead of open sources.
- For STIs, social stigma is said to perversely increase risky behavior; normalization of testing/treatment is framed as harm reduction.
Mechanisms, Cognition, and “Free Will”
- Rabies “hydrophobia” debated: is it primarily pain on swallowing plus panic, or a more specific fear of water? Both behavioral and neurological symptoms are cited.
- Lively argument over whether panic is learned vs instinctive, and whether pain alone can induce panic.
- Broader worry that cognitive and personality traits (religiosity, moral views, “political views”) may be shaped by pathogens or brain disorders, with links to epilepsy and psychosis.
- Drugs (SSRIs, birth control, food scarcity) also noted as behavior-modifying, blurring lines between “natural” and “manipulated” behavior.
Other Species: Insects, Mantises, Turtles
- Mantises’ attraction to horizontally polarized light is linked to horsehair worms’ need for water; mechanism of how the worm tweaks existing polarization vision remains unclear.
- Other parasite strategies: insects climbing plants to be eaten by birds; ants climbing grass for liver flukes; cordyceps making insects clamp onto branches.
- Artificial lighting misguides sea turtle hatchlings; some propose using AI/ML and drones to predict hatching and guide them, while others object to “AI” being injected into every topic.
Microbiome, Diet, and “Memetic” Parasites
- Speculation that gut microbes or yeast might drive sugar cravings; some say this is a serious research avenue, others call its status “not known” but plausible.
- Ideas and ideologies are likened to biological parasites (memes) that spread by altering host behavior, sometimes with lethal consequences.
- Recommended reading: books on parasites and extended phenotypes, plus various pop-culture portrayals (sci-fi, games, TV).