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Symbiotic relationships within ecosystems
Review your understanding of mutualism, commensalism, and parasitism in this free article aligned to AP standards.
Key points
- The term symbiosis describes close, long-term interactions between individuals of two different species. Types of symbiosis include mutualism, commensalism, and parasitism.
- Mutualism occurs when two organisms of different species provide each other with resources or services, and both organisms benefit. For example, sea anemones and clownfish share a mutualistic relationship in which anemones provide shelter and protection, and clownfish provide nutrients in the form of waste.
- Commensalism is an interaction between species where one organism benefits, and the other organism is not significantly affected. A barnacle and a whale exhibit commensalism when the barnacle attaches to the whale. The whale is unaffected, while the barnacle is able to gather food from the water as the whale swims.
- Parasitism is an interaction between species in which one organism—the parasite—benefits by living and feeding on another organism—the host—who is harmed but not immediately killed. For example, a sea lamprey is a parasite that attaches itself to the body of a host fish and consumes the fish's body fluids. The lamprey draws nourishment from the fish, and the fish gradually weakens over time.
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are parasites needed?(11 votes)
That question has many answers, depending on perspective.
(a) parasites are a part of keeping a balanced ecosystem.
(b) parasites as a whole are bad.
(c) the only bad parasites are the ones that don't have a predator to keep them in check.
(d) parasites that are introduced into a different ecosystem (an invasive species) are bad.
From my perspective, humans who do not respect the Earth are parasites.
I'd rather live among the beasts of the Earth than among humans...(20 votes)
- can some parasites benefit the host ?(5 votes)
No. By definition, parasites are harmful to their hosts. When the host benefits, it would be considered mutualism or commensalism, depending on whether both sides benefit or one does and the other isn't affected.(12 votes)
- is there a relationship where both species hurt each other?(3 votes)
- Yes, these relationships are called competition where two or more species utilize a shared resource and limit each other's ability to use it. As a result, both species may experience reduced fitness and/or growth rates.(6 votes)
What's the difference between parasitism and predation? Are parasites predators too? Are their hunting strategies defined differently?(3 votes)
Predation is defined as an interaction where one organism, the predator, kills the other organism, the prey, for consumption and energy.
On the other hand, parasitism is where one organism, the parasite, lives on or in the other organism, the host, and harms them by consuming their host's food, for example, a tapeworm parasite living in the host's digestive tract.
The key difference is that in predation, the predator always kills the prey. The mouse is not alive after the snake eats it kinda thing. In parasitism, the parasite, yes is harming the host, but not to the extent of the host's death. They do not want the host to die, as that would mean they have to find a new host. In actuality, when a parasite's host is killed off, this is when the parasite is most vulnerable. Think of a mosquito. While they take your blood as food, they don't kill you, unless they may have transmitted malaria, which is completely unrelated.(5 votes)
can mutualism turn into parasitism(4 votes)
No, it shouldn't be able to suddenly change so much.(2 votes)
- are these real people fr?(4 votes)
- Is there a relationship that both species can end up hurting each other instead of benefiting ?(2 votes)
- Yes. That is called competition.(-/-) If you want something and the same species gets more of what you want, that is bad for you; and vice versa. Example:Let's say that you are a plant that is getting sunlight. If another plant takes more sunlight than you, it's bad for you; and vice versa. Hope this helped!(4 votes)
Can parasites consume different ways without harming the environment?(3 votes)- Yes, i believe that would fall under the commensalism category.(1 vote)
does a anemone actually sting(2 votes)
An anemone does actually sting. It does this with a bunch of pointed cells covering the surface of its body. They put microscopic incisions in the skin of fish crustations and people if they're not careful.(3 votes)
- How do fish stay alive in the sea.(2 votes)
- The fish's gills allow it to breathe underwater.These gills capture oxygen in the water allowing the remainder to pass through(3 votes)
