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Marvels of Nature

Paul B3Paul B3 Posts: 3,146

Two or three weeks ago , there was a thread on here relating to Aconitum (Monkshood) aphids .

I looked these up , and they were the blue-bodied Delphiniobium aphids , which also attack Delphiniums (would you guess) ? What I found amazing about these creatures was the fact they absorb the toxins from the plant , thus making themselves toxic to predators .

Being bright blue , they make no attempt to conceal themselves , unlike most other aphids , and bask in broad daylight on the upper leaf surfaces , almost 'knowing' they are impervious to attack !

Would this be a classic case of symbiosis in nature ? I find this whole concept absolutely fascinating .

I know complex relationships exist involving plants/birds/insects etc . but these are nearly always associated with warmer climes and more hostile environments than the relatively benign European climate .

Does anyone here know of similar scenarios involving our more common garden plants ?

Your replies will be most welcome .


  • josusa47josusa47 Posts: 3,530

    Not garden plants, but cinnabar moth caterpillars are one of the few creatures that can eat ragwort with impunity.  The toxins accumulate in their bodies, and they advertise their toxicity by being striped in black and bright orange.

  • it is not symbiosis as the plant gets nothing out of it - it is parasitism. One example of symbiosis in the garden is aphids and ants - ants feed on the aphids' secretions of honeydew, while the ants protect the aphids from predators.

  • I have found a White |Ermine moth a couple of times in the garden, and reading up on it, found that it is another that can sequester alkaloids from ragwort  or other plants, though ragwort is not its main food. It can afford to be bright white and highly visible because of its toxicity.

    The book I read also suggested that having a fairly high population density meant that sacrifical victims could help to 'educate' predators and thus protect the rest of the population!

    A more balanced symbiotic relationship would be the one where ants  remove the sweet sticky coating from  cyclamen  seeds, and help to extend the range of an individual plant when the seeds themselves are left uneaten.

  • punkdocpunkdoc Posts: 14,969

    Symbiosis: Mutualism, Commensalism And Parasitism

    The species in an ecosystem will interact in different ways. These interactions may have positive, neutral or negative impacts on the species involved.

    The term symbiosis can be used to broadly refer to these types of relationships as it directly translates to mean living together (sym: with; bio: life).

    Symbiosis is the ecological relationship between two or more organisms living closely together with some form of feeding relationship involved. The three main symbiotic relationships are:

    Mutualism, where both organisms benefit.

    Commensalism, where one organism benefits while the other organism is not harmed.

    Parasitism, where one organism benefits and causes harm to the other organism.


    This is a beneficial relationship to both partners of different species living together. For example a bee and a pollinating flower. The bee gains nectar from the flower for survival, as it uses the bee to carry its pollen to other flowers. So both organisms living together benefit from their existence.


    The association of two or more partners living together, where only one benefits from the partnership and the other remains unharmed.  An example of this is the relationship between a sea anemone with and a clown fish. The anemone travels with the fish on route to its destination and the fish remains unharmed.


    Parasites are completely dependent on a host for survival. The relationship is beneficial to one, and harmful to the other.  Parasites may live outside or inside a host; they are called ectoparasites (the prefix ecto means outside) and endoparasites (theprefix endo means inside). An example of the endoparasite is the tapeworms which live in the digestive systems of its host. Examples of ectoparasites are ticks and lice.

    How can you lie there and think of England
    When you don't even know who's in the team

    S.Yorkshire/Derbyshire border
  • Great summary from Punkock. There is a form of Mutalism called co-dependence this is where both organisms co-exist & one  cannot live without the other. I think plant roots & Microrrhizal fungi may fall into this category, the fungi makes nutrients available to the plant and the plant provides sugars to the fungus. A more obvious one is all Eukaryotic cells and Mitochondria but that is getting a bit technical.

    AB Still learning

  • One example of mutualism is Lichens - algae and bacteria living together, possibly with other organisms to form an even more complicated system. 

  • Paul B3Paul B3 Posts: 3,146

    Thankyou all for your answers . As someone stated recently to a new 'poster' ; "there is a vast amount of knowledge on this forum" ! There certainly is image !!

  • josusa47josusa47 Posts: 3,530

    A parasite harms its host but not enough to kill it, since it would thereby lose its livelihood.  There are also parasitoids, which are temporarily dependent on a host during one phase of their lives.  For example, some small wasps lay eggs in a living caterpillar.  When they hatch, the wasp larvae feed on the caterpillar's innards until they are ready to pupate, by which time the caterpillar is at death's door.  

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