Track topics on Twitter Track topics that are important to you
Parasitoids of herbivorous insects have frequently evolved specialized lineages exploiting hosts occurring on different plants. This study investigated whether host specialization is also observed when closely related parasitoids exploit herbivorous hosts sharing the same host plant. The question was addressed in economically relevant aphid parasitoids of the Lysiphlebus fabarum group. They exploit two aphid species (Aphis fabae cirsiiacanthoides and Brachycaudus cardui), co-occurring in mixed colonies (syntopy) on the spear thistle (Cirsium vulgare). Two morphologically distinguishable parasitoid lineages of the genus Lysiphlebus were observed and each showed virtually perfect host specialization on one of the two aphid species in this system. From A. f. cirsiiacanthoides, only females emerged that morphologically belonged to Lysiphlebus cardui, while males and females belonging to L. fabarum hatched from B. cardui. Microsatellite analyses indicated clear genetic differentiation of L. fabarum and L. cardui. L. cardui comprised only two distinct asexual lineages, one of which predominated throughout the area investigated. Population genetic analysis of sexual L. fabarum showed evidence for relatively strong spatial structuring and limited dispersal ability. Hyperparasitoids emerged from a large proportion of aphid mummies. One species, Pachyneuron aphidis, was significantly associated with B. cardui/L. fabarum mummies, indicating that host specialization may even extend to the trophic level above parasitoids.
Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
This article was published in the following journal.
Name: Bulletin of entomological research
Specialization is a central concept in ecology and one of the fundamental properties of parasitoids. Highly specialized parasitoids tend to be more efficient in host-use compared to generalized parasi...
Insects are often attacked by multiple natural enemies, imposing dynamic selective pressures for the development and maintenance of enemy-specific resistance. Pea aphids (Acyrthosiphon pisum) have eme...
We tested the hypothesis that avian haemosporidian (malaria) parasites specialize on hosts that can be characterized as predictable resources at a site in Amazonian Ecuador. We incorporated host phylo...
Host-associated races of phytophagous insects provide a model for understanding how adaptation to a new environment can lead to reproductive isolation and speciation, ultimately enabling us to connect...
Extreme specialization is a common phenomenon in antagonistic biotic interactions but it is quite rare in mutualistic ones. Indeed, bee specialization on a single flower species (monolecty) is a quest...
Recently, we have shown functional resonance imaging (fMRI) that variations in signal induced by a language task were significantly lower in a semantic region of the left hemisphere (compr...
Clinical evaluation of stenfilcon A compared with narafilcon A and delefilcon A This is a total 120 subject, randomized, open label, bilateral wear, two week crossover study (each lens fo...
The neuropeptide oxytocin (OXT) has been identified as a key modulator of human social behavior and it has been recently shown that OXT also contributes to pair-bonding in men. However, it...
The purpose of this study is to demonstrate whether, in patients diagnosed with Vertical Heterophoria, the symptoms of dizziness, headache and / or anxiety are reduced or eliminated when ...
This pilot phase II trial studies how well carfilzomib works in treating patients with chronic graft-versus-host disease. Chronic graft-versus-host disease is a complication of a donor bon...
An immunological attack mounted by a graft against the host because of tissue incompatibility when immunologically competent cells are transplanted to an immunologically incompetent host; the resulting clinical picture is that of GRAFT VS HOST DISEASE.
An occupation limited in scope to a subsection of a broader field.
A specific pair GROUP C CHROMSOMES of the human chromosome classification.
A specific pair of GROUP C CHROMSOMES of the human chromosome classification.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.