What is obligate species?

Obligate species (Latin obligatus, "binding") is an organism that has an absolute requirement for another species to survive and complete its life cycle, unlike a symbiotic relationship. For instance, certain fungi must grow on specific plant hosts to obtain organic nutrients they cannot synthesize themselves.

Examples of obligate species:

1. Mistletoe (Phoradendron spp.) is an obligate hemiparasite that grows on the branches of trees and obtains water, nutrients, and minerals from its host.

2. Clownfish (Amphiprioninae) are obligate mutualists that live among the stinging tentacles of sea anemones. The clownfish provide protection from predators to the sea anemone, while the sea anemone provides food and shelter to the clownfish.

3. Striped bass (Morone saxatilis) is an obligate anadromous fish that requires both freshwater and saltwater to complete its life cycle.

4. Monarch butterflies (Danaus plexippus) are obligate herbivores that depend solely on milkweed plants (Asclepias spp.) for food and reproduction.

5. Lianas (woody vines) are obligate climbers that require the support of trees or other structures to grow vertically.