Nejvíce citovaný článek - PubMed ID 17988897
The balance between risk and benefit of exploiting resources drives life-history evolution in organisms. Predators are naturally recognized as major drivers of the life-history evolution of their prey. Although prey may also influence the life-history evolution of their predators in the context of an evolutionary arms race, there is far more evidence of the role of predators than of prey.The goal of this study was to investigate the role of prey in life-history evolution of predators using ladybird beetle predators of aphids and coccids. These particular ladybirds and their prey were chosen because literature shows that the pace of life of aphids is faster than that of coccids and this difference is reflected in the life histories of the ladybirds that specialize on feeding on aphids or coccids.Thirty-four species of ladybird predators of aphids and eight of coccids belonging to five different tribes were collected and reared in the laboratory. The females were weighed as well as their eggs, and their reproductive investment estimated as the number of ovarioles. Phylogenetic relatedness was controlled for in the statistical analyses.Controlling for female mass revealed that ladybird predators of aphids lay bigger eggs than ladybird predators of coccids. This difference is not influenced by phylogenetic relatedness but only by the type of prey eaten. We suggest that ladybird predators of coccids lay smaller eggs because neonate larvae do not have to search, catch, and subdue prey. Both types of ladybirds have a similar reproductive investment relative to their body mass when phylogeny is controlled for.Recognizing the influence of prey on the life-history evolution of predators is important for understanding food web dynamics. From an applied perspective, this fine evolutionary tuning of prey-predator relationships should be used to guide and increase the efficiency of biological control programs.
- Klíčová slova
- aphids, coccids, egg mass, insect predators, ladybird beetles, life‐history evolution, ovariole number, reproductive investment,
- Publikační typ
- časopisecké články MeSH
BACKGROUND: The tribe Coccinellini is a group of relatively large ladybird beetles that exhibits remarkable morphological and biological diversity. Many species are aphidophagous, feeding as larvae and adults on aphids, but some species also feed on other hemipterous insects (i.e., heteropterans, psyllids, whiteflies), beetle and moth larvae, pollen, fungal spores, and even plant tissue. Several species are biological control agents or widespread invasive species (e.g., Harmonia axyridis (Pallas)). Despite the ecological importance of this tribe, relatively little is known about the phylogenetic relationships within it. The generic concepts within the tribe Coccinellini are unstable and do not reflect a natural classification, being largely based on regional revisions. This impedes the phylogenetic study of important traits of Coccinellidae at a global scale (e.g. the evolution of food preferences and biogeography). RESULTS: We present the most comprehensive phylogenetic analysis of Coccinellini to date, based on three nuclear and one mitochondrial gene sequences of 38 taxa, which represent all major Coccinellini lineages. The phylogenetic reconstruction supports the monophyly of Coccinellini and its sister group relationship to Chilocorini. Within Coccinellini, three major clades were recovered that do not correspond to any previously recognised divisions, questioning the traditional differentiation between Halyziini, Discotomini, Tytthaspidini, and Singhikaliini. Ancestral state reconstructions of food preferences and morphological characters support the idea of aphidophagy being the ancestral state in Coccinellini. This indicates a transition from putative obligate scale feeders, as seen in the closely related Chilocorini, to more agile general predators. CONCLUSIONS: Our results suggest that the classification of Coccinellini has been misled by convergence in morphological traits. The evolutionary history of Coccinellini has been very dynamic in respect to changes in host preferences, involving multiple independent host switches from different insect orders to fungal spores and plants tissues. General predation on ephemeral aphids might have created an opportunity to easily adapt to mixed or specialised diets (e.g. obligate mycophagy, herbivory, predation on various hemipteroids or larvae of leaf beetles (Chrysomelidae)). The generally long-lived adults of Coccinellini can consume pollen and floral nectars, thereby surviving periods of low prey frequency. This capacity might have played a central role in the diversification history of Coccinellini.
- Klíčová slova
- Coccinelloidea, Diet shifts, Evolution, Feeding strategies, Food preferences, Ladybugs, Taxonomy,
- MeSH
- biologická evoluce MeSH
- brouci klasifikace genetika růst a vývoj fyziologie MeSH
- fylogeneze MeSH
- larva fyziologie MeSH
- molekulární evoluce MeSH
- predátorské chování MeSH
- preference v jídle MeSH
- zavlečené druhy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
An updated checklist of the Coccinellidae species of the former subfamily Sticholotidinae recorded from Iran is provided. Eleven species are reported: two species classified presently in the subfamily Microweiseinae (in the genera Paracoelopterus Normand, 1936 and Serangium Blackburn, 1889), and nine species classified in the tribe Sticholotidini of the subfamily Coccinellinae (in the genera Coelopterus Mulsant & Rey, 1852 and Pharoscymnus Bedel, 1906). Pharoscymnus smirnovi Dobzhansky, 1927 is removed from the list of the Coccinellidae of Iran. Distribution of species in Iranian provinces is presented. Data concerning their host plants along with their prey species are also included when known. Morphological features of two rarely collected and poorly known species of Iranian fauna, Pharoscymnus brunneosignatus Mader, 1949 and Pharoscymnus pharoides (Marseul, 1868) are diagnosed and illustrated.
- Klíčová slova
- Coccinelloidea, Microweiseinae, Sticholotidini, distribution, host plants, prey species, updated checklist,
- Publikační typ
- časopisecké články MeSH
Mitochondrial genomes are readily sequenced with recent technology and thus evolutionary lineages can be densely sampled. This permits better phylogenetic estimates and assessment of potential biases resulting from heterogeneity in nucleotide composition and rate of change. We gathered 245 mitochondrial sequences for the Coleoptera representing all 4 suborders, 15 superfamilies of Polyphaga, and altogether 97 families, including 159 newly sequenced full or partial mitogenomes. Compositional heterogeneity greatly affected 3rd codon positions, and to a lesser extent the 1st and 2nd positions, even after RY coding. Heterogeneity also affected the encoded protein sequence, in particular in the nad2, nad4, nad5, and nad6 genes. Credible tree topologies were obtained with the nhPhyML ("nonhomogeneous") algorithm implementing a model for branch-specific equilibrium frequencies. Likelihood searches using RAxML were improved by data partitioning by gene and codon position. Finally, the PhyloBayes software, which allows different substitution processes for amino acid replacement at various sites, produced a tree that best matched known higher level taxa and defined basal relationships in Coleoptera. After rooting with Neuropterida outgroups, suborder relationships were resolved as (Polyphaga (Myxophaga (Archostemata + Adephaga))). The infraorder relationships in Polyphaga were (Scirtiformia (Elateriformia ((Staphyliniformia + Scarabaeiformia) (Bostrichiformia (Cucujiformia))))). Polyphagan superfamilies were recovered as monophyla except Staphylinoidea (paraphyletic for Scarabaeiformia) and Cucujoidea, which can no longer be considered a valid taxon. The study shows that, although compositional heterogeneity is not universal, it cannot be eliminated for some mitochondrial genes, but dense taxon sampling and the use of appropriate Bayesian analyses can still produce robust phylogenetic trees.
- Klíčová slova
- PhyloBayes, RY coding, long-range PCR, mitogenomes, mixture models, rogue taxa,
- MeSH
- brouci klasifikace genetika MeSH
- fylogeneze * MeSH
- genetická heterogenita * MeSH
- genom hmyzu * MeSH
- genom mitochondriální * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH