Summary
Parasites such as ticks and tapeworms live on or in hosts, harming them.
In depth
Ectoparasites (fleas, lice, ticks) live outside; endoparasites (tapeworms, flukes) live inside. Parasites often have complex life cycles with intermediate hosts, high reproduction and specialised attachment organs.
Parasites often manipulate hosts. Hosts evolve resistance. Parasitism is extremely common.
Remember: definitive hosts hold the adult parasite.
Parasites make up a large share of species (some estimate over 40 percent) and have effects on host behaviour, populations and food webs. Adaptations include hooks, suckers, reduced digestive systems (tapeworms), high reproductive output and evasion of immunity. Life cycles may involve intermediate and definitive hosts, as with liver flukes using snails and ants. Parasites can manipulate hosts: Toxoplasma gondii reduces fear of cats in rodents, hairworms drive crickets to water, and Leucochloridium makes snail tentacles look like caterpillars.
Brood parasites such as cuckoos lay eggs in other birds' nests, leading to arms races with hosts that learn to reject eggs. Social parasites exploit ant colonies. Parasites can regulate populations and keep diversity high. Human infection includes malaria, schistosomiasis, hookworm and lice.
Frequently asked questions
What is Parasitism in Animals?
Parasites such as ticks and tapeworms live on or in hosts, harming them.
Which area of biology covers Parasitism in Animals, and how advanced is it?
Parasitism in Animals is one of the 53 topics in Zoology & Animal Diversity. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Flatworms, Vertebrates and Invertebrates, Bioluminescence.
Why does Parasitism in Animals matter?
Parasite control improves health and food production worldwide.
Can you give an example of Parasitism in Animals?
Toxoplasma gondii can alter rodent behaviour.
What should I learn before Parasitism in Animals?
Work through the Beginner topics in Zoology & Animal Diversity first, such as Animal Kingdom, Vertebrates and Invertebrates, Sponges, then return to Parasitism in Animals. Intermediate topics assume the Beginner vocabulary.
What topics are related to Parasitism in Animals?
The closest topics to Parasitism in Animals are Flatworms, Vertebrates and Invertebrates, Bioluminescence, Island Gigantism and Dwarfism. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Parasitism in Animals?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Parasitism in Animals. To practise the whole of Zoology & Animal Diversity, use the Zoology & Animal Diversity quiz.
How is Parasitism in Animals different from Flatworms?
Parasitism in Animals: Parasites such as ticks and tapeworms live on or in hosts, harming them. Flatworms: Soft-bodied, bilaterally symmetric worms with no body cavity, including tapeworms and flukes. Read both side by side and note what each one explains.
How should I study Parasitism in Animals step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Flatworms and explain the difference aloud. Finally, take the Zoology & Animal Diversity quiz and come back to this page for any question you miss.