500
hyperdiverse apocritan parasitoid lineages. The ten parasite taxa differ from the
seven parasitoid taxa in five basic ways that involve life-history features and disposition of their hosts. Of parasitoids, the major groups are mantispids (Neuroptera),
with 1 origination; beetles, with 10 originations; twisted-wing parasites
(Strepsiptera), with a single origination; flies, with approximately 60 originations;
caddisflies (Trichoptera) and moths (Lepidoptera), with 1 and 2 originations respectively; and wasps with either 1 or 2 originations, depending on the authority. The
bulk of parasitoid diversity is Hymenoptera, accounting for 75% of all extant parasitoid species, consisting of 92 families in 17 superfamilies, and containing 63% of
all extinct and extant families (Tables 11.1 and 11.2). Hymenoptera were the major
driver of the Mid Mesozoic Parasitoid Revolution (MMPR), resulting in a dramatic
expansion of parasitoidic lineages during the Middle Jurassic to Early Cretaceous.
Modern terrestrial food webs are important for understanding the MMPR. Bottom–
up food webs explained by the resource concentration hypothesis, account for the
pre-MMPR interval leading up to the latest Early Jurassic. Four biotas typical of
pre-MMPR time are the Madygen, Molteno, Beishan–Shangtu and Solite biotas, of
Middle to Late Triassic age. Once parasitoids originated during the late Early
Jurassic, the body-fossil record indicates that their subsequent family-level diversity
is subdivided into four temporal phases, each phase of which is characterized by a
stepwise increase from the previous diversity level of particular parasitoid clades or
groups (Fig. 11.19). During MMPR Phase 1 (Toarcian to Valanginian stages) and
Phase 2 (Hauterivian to Aptian stages), a shift ensued from pre-MMPR bottom–up
regulation of food webs to MMPR top–down regulation of food webs. This shift is
explained by the trophic cascade hypothesis and the trophic efficiency of parasitoids
compared to predators (Slansky 1986; Godfray 1994; Harvey et al. 2009). Four
biotas typical of the MMPR time interval are the Yanliao, Karatau, Purbeck and
Jehol biotas. Two case studies involving early hymenopteran parasitoid clades,
Stephanoidea and Evanioidea, document the initial radiation of MMPR lineages
that contain lineages that currently are mostly extinct or relict. The post-MMPR
interval consisted of Phase 3 (Cenomanian to Lutetian stages) and Phase 4 (Bartonian
Stage to recent), during which there was further consolidation of insect parasitoid
taxa in food webs. Four biotas illustrative of the post-MMPR interval are Myanmar
Amber, Canadian Amber, Messel and Dominican Amber biotas.
There appears to be no association between the MMPR and angiosperm diversity. Rather, three clade-specific innovations are indicated: (1) notably the hostseeking, triungulin larva in Neuroptera, Coleoptera and Strepsiptera, and planidium
larva in Diptera; (2) the extrudable, telescoped ovipositor in Diptera; and (3) the
long, valved and flexible ovipositor in Hymenoptera. The likely cause of the MMPR
required multiple steps of biological organization that produced a series of events
from the late Early Jurassic to the late Early Cretaceous. First, was the necessity of
the holometabolous condition. Second, was development of the three key innovations of a drilling ovipositor in apocritan Hymenoptera, the host-seeking triungulin
and planidium first-instar stages in several holometabolan lineages, and the telescoped ovipositor of Diptera. Third, was reformatting the ecological structure of
terrestrial ecosystems from resource driven to trophic-cascade driven food webs
C. C. Labandeira and L. Li
hyperdiverse apocritan parasitoid lineages. The ten parasite taxa differ from the
seven parasitoid taxa in five basic ways that involve life-history features and disposition of their hosts. Of parasitoids, the major groups are mantispids (Neuroptera),
with 1 origination; beetles, with 10 originations; twisted-wing parasites
(Strepsiptera), with a single origination; flies, with approximately 60 originations;
caddisflies (Trichoptera) and moths (Lepidoptera), with 1 and 2 originations respectively; and wasps with either 1 or 2 originations, depending on the authority. The
bulk of parasitoid diversity is Hymenoptera, accounting for 75% of all extant parasitoid species, consisting of 92 families in 17 superfamilies, and containing 63% of
all extinct and extant families (Tables 11.1 and 11.2). Hymenoptera were the major
driver of the Mid Mesozoic Parasitoid Revolution (MMPR), resulting in a dramatic
expansion of parasitoidic lineages during the Middle Jurassic to Early Cretaceous.
Modern terrestrial food webs are important for understanding the MMPR. Bottom–
up food webs explained by the resource concentration hypothesis, account for the
pre-MMPR interval leading up to the latest Early Jurassic. Four biotas typical of
pre-MMPR time are the Madygen, Molteno, Beishan–Shangtu and Solite biotas, of
Middle to Late Triassic age. Once parasitoids originated during the late Early
Jurassic, the body-fossil record indicates that their subsequent family-level diversity
is subdivided into four temporal phases, each phase of which is characterized by a
stepwise increase from the previous diversity level of particular parasitoid clades or
groups (Fig. 11.19). During MMPR Phase 1 (Toarcian to Valanginian stages) and
Phase 2 (Hauterivian to Aptian stages), a shift ensued from pre-MMPR bottom–up
regulation of food webs to MMPR top–down regulation of food webs. This shift is
explained by the trophic cascade hypothesis and the trophic efficiency of parasitoids
compared to predators (Slansky 1986; Godfray 1994; Harvey et al. 2009). Four
biotas typical of the MMPR time interval are the Yanliao, Karatau, Purbeck and
Jehol biotas. Two case studies involving early hymenopteran parasitoid clades,
Stephanoidea and Evanioidea, document the initial radiation of MMPR lineages
that contain lineages that currently are mostly extinct or relict. The post-MMPR
interval consisted of Phase 3 (Cenomanian to Lutetian stages) and Phase 4 (Bartonian
Stage to recent), during which there was further consolidation of insect parasitoid
taxa in food webs. Four biotas illustrative of the post-MMPR interval are Myanmar
Amber, Canadian Amber, Messel and Dominican Amber biotas.
There appears to be no association between the MMPR and angiosperm diversity. Rather, three clade-specific innovations are indicated: (1) notably the hostseeking, triungulin larva in Neuroptera, Coleoptera and Strepsiptera, and planidium
larva in Diptera; (2) the extrudable, telescoped ovipositor in Diptera; and (3) the
long, valved and flexible ovipositor in Hymenoptera. The likely cause of the MMPR
required multiple steps of biological organization that produced a series of events
from the late Early Jurassic to the late Early Cretaceous. First, was the necessity of
the holometabolous condition. Second, was development of the three key innovations of a drilling ovipositor in apocritan Hymenoptera, the host-seeking triungulin
and planidium first-instar stages in several holometabolan lineages, and the telescoped ovipositor of Diptera. Third, was reformatting the ecological structure of
terrestrial ecosystems from resource driven to trophic-cascade driven food webs
C. C. Labandeira and L. Li