In contrast, baleen whales eat millions of microscopic plankton at once, swallowing them alive.Seed and egg predation are true predation, as seeds and eggs are potential organisms.
It could also constitute a chase, stalking, or attack of prey.While a grazing species such as an elephant may travel many kilometers in a single day, grazing on many plants in the process, parasites form very close associations with their hosts, usually having only one or at most a few in their lifetime.This close living arrangement may be described by the term symbiosis, "living together", but unlike mutualism the association significantly reduces the fitness of the host.Parasitoids are organisms living in or on their host and feeding directly upon it, eventually leading to its death.They are much like parasites in their close symbiotic relationship with their host or hosts.Thus predation is often, though not always, carnivory.
Other categories of consumption are herbivory (eating parts of plants), fungivory (eating parts of fungi), and detritivory (the consumption of dead organic material). For example, some parasites prey on their host and then lay their eggs on it, for their offspring to feed on it while it continues to live, or on its decaying corpse after it has died.
The key characteristic of predation is the predator's direct impact on the prey population.
Selective pressures (coevolution) imposed on one another often leads to an evolutionary arms race between prey and predator, resulting in various antipredator adaptations.
Predators need not eat prey entirely; for example, some predators cannot digest bones.
Some may eat only part of an organism, but still consistently cause its death.
Lepidoptera (butterfly and moth) larvae may feed parasitically on only a single plant, or they may graze on several nearby plants.