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difference of a food web is based on the trophic interactions of the consumption of
plants versus the consumption of animals. Thus, the exclusion of herbivory from parasitism makes good ecological sense. An alternative view is that parasitism is a perplexing concept difficult to define owing to conceptual difficulties in separating parasitism
from herbivory and from the insensible trophic gradations among commensalism,
mutualism and symbiosis (Araújo et al. 2003)—a view that is not taken here.
11.2.3 Parasitoidism
Parasitoidism is a trophic interaction whereby a free-living adult has a dispersive
stage whose parasitic larva gradually consumes and eventually obligately kills its
host from within or without upon the parasitoid emerging as an adult (Gauld and
Bolton 1988; Morris 1998). The feeding behavior of parasitoids can be considered
intermediate between that of a predator and a parasite (Knutson and Berg 1966).
Although a parasitoid does kill its host, analogous to a predator killing its prey, it
also feeds and has life habits like that of a parasite, existing in intimate association
and extracting in incremental fashion nutrition from its host (Askew 1971). The
definition of what constitutes a parasitoid has undergone many changes in the
century- long history of the concept. These shifts in definition are probably why
there are several categories of parasitoids.
11.2.4 Parasitoidism: A History of the Term
Reutter (1913) was the first to coin the term parasitoid, which he defined, insightfully, as a feeding behavior intermediate between predation and parasitism. The
term was redefined by Waage and Greathead (1986), who detailed the parasitoid life
history as follows.
Adult female parasitoids are free-living, feed on nectar, pollen or as predators and forage
actively for their arthropod hosts on plants and other substrates. Usually, on locating a host,
the female lays one or more eggs on or in it, and the ensuing larvae consume the host tissue,
killing the host in the process.
By contrast, Eggleton and Gaston (1990) mentioned that Price (1984) offered a
more unambiguous definition based on a circumscribed definition of parasitoid lifehistory patterns.
A species of insect that requires and eats only one animal in its life span by living parasitically as a larva on a host; but the adult is free-living and may ultimately kill many hosts by
leaving eggs or larvae near or on the host that consume the host.
A few years later Gauld and Bolton (1988) provided a more succinct definition with
a greater economy of words.
Parasitoids are insects whose larvae develop by feeding on or within an arthropod host, and
this host individual is almost always killed by the developing parasitoid larva.
C. C. Labandeira and L. Li
difference of a food web is based on the trophic interactions of the consumption of
plants versus the consumption of animals. Thus, the exclusion of herbivory from parasitism makes good ecological sense. An alternative view is that parasitism is a perplexing concept difficult to define owing to conceptual difficulties in separating parasitism
from herbivory and from the insensible trophic gradations among commensalism,
mutualism and symbiosis (Araújo et al. 2003)—a view that is not taken here.
11.2.3 Parasitoidism
Parasitoidism is a trophic interaction whereby a free-living adult has a dispersive
stage whose parasitic larva gradually consumes and eventually obligately kills its
host from within or without upon the parasitoid emerging as an adult (Gauld and
Bolton 1988; Morris 1998). The feeding behavior of parasitoids can be considered
intermediate between that of a predator and a parasite (Knutson and Berg 1966).
Although a parasitoid does kill its host, analogous to a predator killing its prey, it
also feeds and has life habits like that of a parasite, existing in intimate association
and extracting in incremental fashion nutrition from its host (Askew 1971). The
definition of what constitutes a parasitoid has undergone many changes in the
century- long history of the concept. These shifts in definition are probably why
there are several categories of parasitoids.
11.2.4 Parasitoidism: A History of the Term
Reutter (1913) was the first to coin the term parasitoid, which he defined, insightfully, as a feeding behavior intermediate between predation and parasitism. The
term was redefined by Waage and Greathead (1986), who detailed the parasitoid life
history as follows.
Adult female parasitoids are free-living, feed on nectar, pollen or as predators and forage
actively for their arthropod hosts on plants and other substrates. Usually, on locating a host,
the female lays one or more eggs on or in it, and the ensuing larvae consume the host tissue,
killing the host in the process.
By contrast, Eggleton and Gaston (1990) mentioned that Price (1984) offered a
more unambiguous definition based on a circumscribed definition of parasitoid lifehistory patterns.
A species of insect that requires and eats only one animal in its life span by living parasitically as a larva on a host; but the adult is free-living and may ultimately kill many hosts by
leaving eggs or larvae near or on the host that consume the host.
A few years later Gauld and Bolton (1988) provided a more succinct definition with
a greater economy of words.
Parasitoids are insects whose larvae develop by feeding on or within an arthropod host, and
this host individual is almost always killed by the developing parasitoid larva.
C. C. Labandeira and L. Li