Loxdale's research demonstrated that as the tansy aphid, parasitized by its specialist wasp parasitoid Lysiphlebus hirticornis, underwent increased genetic variation, so did that of its parasitoid. This suggested a fine-grained co-evolutionary tracking to be in operation. Such a scenario is supportive of the Red Queen hypothesis, whereby a host organism is attempting to evolve away from its antagonist, which is meanwhile co-evolving in order to retain the ability to attack it, i.e. keep pace with it in an ecological-evolutionary sense. Loxdale also determined the insecticide resistance status of the serious agricultural pest the peach-potato aphid, Myzus persicae. From this work, the spatial and temporal dynamics of this important pest aphid could be followed, thereby leading to more rational and effective control measures in the field. Loxdale has written reviews on absence of strict genetic uniformity in populations of clonal organisms such as aphids. This lack of uniformity is due to the rapid rate of mutation resulting from various mechanisms amplified by the huge reproductive potential of the animals concerned, e.g., not only do aphids show ‘telescoping of generations’ such that an adult asexual female has her children and grandchildren within her, but also the ability to produce a large number of asexual copies in a short time. Hence, a single aphid can, in theory produce enough offspring to cover the entire planet to a depth of many kilometres in a single growing season! This of course has serious potential consequences for the agricultural, horticultural and forestry industries worldwide. Loxdale has also co-authored overviews on several key areas of biological thought and research. These include the migration and dispersal of insects in relation to their genotype and habitat; intra-clonal genetic variation; rapid evolution in insect populations due to various genetic-ecological mechanisms; population proteomics; and on the improbability of generalism in nature, with special reference to insects The consensus of these articles is that the act of filling a new ecological niche is the fundamental act of specialization for any new species or sub-specific population. Whilst some species may be polyphagous to varying degrees, nevertheless diet breadth tends to involve preference for certain prey items in predatory as well as herbaceous species. Generalism, if it exists, is highly dependent upon an animal's morphology-anatomy, genetics, physiology-biochemistry, and chemistry, especially chemical ecology. This in turn governs the behaviour of the animal concerned and restrains it in terms of its habitat choice and what it can eat. In this light, the age old ‘arms race’ of insect herbivores with plants has led to the plants evolving an armoury of secondary chemical defenses which cause, more often than not, specialisms in terms of host and indeed habitat on the part of the herbivore/s involved. Ultimately, even apparently highly polyphagous species such as the aphid M. persicae, said to attack plants in 40 families, may be because of its highly specialised biochemistry-enzymology.
Poetry
Loxdale has published ten volumes of poetry:
Fascinating Felines
The Eternal Quest: A celebration of nature in poetry
