Transcript Cordyceps
Spotlight on Cordyceps A Fungus using Mind Control on Ants Entering the Ant • Cordyceps is a genus of Sac Fungi that is parasitic to insects • Cordyceps spores attach to the exoskeleton of the ant and begin to grow into hyphae • Hyphae grow into the ant’s body through openings called spiracles that lead into the tubules (trachea) of the ant’s respiratory system Growth and Control of Ant Behavior • Inside the ant, hyphae grow into a mycelium, digesting and absorbing some of the soft tissues but sparing the ant’s organs • When ready to produce spores, the fungus grows into the ant’s brain and interferes with its response to pheromones, chemicals released for communication between ants • If the odd behavior of an infected ant is recognized, another ant can carry it far away from the nest area and discard it • If undetected, the fungus-infested ant climbs up a plant to a leaf of a specific height and attaches securely by its mandibles (appendages near the mouth), to a region near one of the leaf’s veins Spore Production and Distribution • Fungal growth continues inside to stabilize the ant’s exoskeleton and outside to strengthen attachment to the leaf. The fungus also produces antimicrobial substances to repel competitors. • The fungal growth destroys the ant’s brain and a fruiting body grows out of the ant’s head • The fruiting body releases spores, first by asexual reproduction but later by sexual reproduction • Studies have shown that the position of the ant on the underside of leaves of a certain height gives ideal conditions of temperature and humidity for fungal growth and spore production Benefits? • Consider the ecological balance between ant and fungus population sizes • Consider whether the fungus can produce any beneficial substances – Cordycepin is chemically similar to adenosine and shows promise as a possible anti-tumor, anti-fungal and anti-viral drug Questions to Answer 1. To which group of fungi does Cordyceps belong? 2. What part of the fungus first reaches the ant? 3. Which part of the fungal body plan grows within the body of the ant? 4. Interference with which type of chemical signal causes the ant to climb a plant and attach to a leaf? Questions to Answer 5. What do uninfected ants do when encountering an infected ant? 6. What part of the body plan of the fungus grows from the ant’s head? 7. Are spores produced by mitosis or meiosis? 8. What are the current and future beneficial effects to be gained from Cordyceps?