herbivores Flashcards
What is herbivory?
Herbivory is a biological interaction in which an organism, typically an animal, feeds on plants. The herbivore consumes part of the plant material.
What are turf algae?
Turf algae is a short, multispecies assemblage, generally consisting of filamentous macroscopic algae that covers the hard substratum on coral reefs. It is often abundant and can colonize dead coral or compete with live coral.
What is the role of macroalgae in coral reefs?
Macroalgae, which have a different structure from other algae, employ various defense mechanisms (e.g., structural, chemical, and temporal defense) against herbivory. They can compete with corals for space and resources, especially colony-forming cyanobacteria.
What is induced defense in plants?
Induced defense is the production of chemical defenses that can be triggered in response to grazing. These compounds may not be induced by all grazers.
What is special about seagrass?
Seagrass is the only marine flowering plant, with around 60 species in four families. It has returned secondarily to the ocean and has spatial defenses against herbivory, living in structurally simple areas with no shelter for herbivores.
What are the physical defenses of mangroves?
Mangroves have tough leaves that are difficult for herbivores to chew, and they secrete salt onto the surface of their leaves, making them unpalatable to herbivores.
What are the chemical defenses of mangroves?
Mangroves produce tannins (interfere with herbivore digestion), phenolic compounds (reduce herbivore growth and reproduction), and toxic compounds (directly toxic to herbivores).
What are herbivorous fish traits in coral reefs?
Herbivorous fish are diverse and can be grazers, scrapers, or excavators. They have functional roles depending on what and how they eat, with traits like types of teeth, jaws, and stomachs correlating with their feeding strategies.
What are mesograzers?
Mesograzers, like sea slugs, associate with algae for both food and shelter. Some, like sarcoglossan sea slugs, are capable of photosynthesis, absorbing chloroplasts from the algae they feed on (kleptoplasty).
What is the role of large invertebrates in herbivory?
Large invertebrates, such as sea urchins, have smaller territories than vertebrates but can overgraze entire kelp forests when present in high densities.
What can cause phase shifts in coral reef ecosystems?
Phase shifts can occur when large herbivores are overfished. For example, the 1983/84 ciliate disease caused a mass die-off of sea urchins, and combined with storm damage, led to a phase shift from a coral-dominated to a macroalgae-dominated state.
