Insects in biodiversity conservation: some perspectives and directives

Abstract

The Insecta is the most speciose class in the Animal Kingdom. The insect-plant relationship is the dominant biotic interaction, yet plants have many times the biomass of all animals together. The functional significance of insects is enormous, owing to the large numbers of individuals and great intra-and interspecific variety. Lack of human appreciation of importance, coupled with the general disregard and dislike of insects, is an enormous perception impediment to their conservation. This impediment coupled with the taxonomic impediment (at most only about 7-10% of insects are scientifically described) must be overcome for realistic biodiversity conservation. As it is not possible to know all the species relative to the rate at which they are becoming extinct, it is essential to conserve as many biotopes and landscapes as possible. These would be for typical species and communities, as well as for endemic sinks. It is also essential to preserve speciesdynamo areas as an insurance for future biodiversity. Preserved areas must also be linked by movement and gene-flow corridors as much as possible. Recognition, functional importance, taxic uniqueness, typicalness, genetic variation and important behavioural traits place much more emphasis on qualitative biodiversity conservation than on quantitative approaches. Ecological entomologists play a significant double role, suppressing noxious populations on crops, livestock and other products, while at the same time identifying and using beneficial species. There are well-known inherent and environmental risks with many traditional control methods and high risks with the use of genetically engineered biopesticide baculoviruses. Preservation technologies, where individuals are held in suspended animation, must be developed soon. However, such technologies, as with restoration activities such as site restoration, captive breeding, reintroductions and translocations, all require considerable knowledge and economic input to be predictably successful. Ecological restoration involves so many biotic and abiotic interactions in even the simplest of communities, that predictiveness under all potential conditions is virtually unattainable. Instead, there should be strong focus on the preservation and conservation of as many, and as large as possible, pristine and near-pristine unique and typical landscapes as soon as possible.

Global dung beetle response to tropical forest modification and fragmentation: A quantitative literature review and meta-analysis

“…For every modified habitat type and individual forest fragment across 33 studies, we calculated six dung beetle community parameters, standardized relative to intact tropical forest. We openUP (June 2007) organized modified habitats along an approximate disturbance gradient ranging from selectively logged, late and early secondary forest, through agroforestry, tree plantations, to annual crops, cattle pastures and clear-cuts. Secondary forests, selectively logged forest and agroforests supported rich communities with many intact forest species, while cattle pastures and clear-cuts contained fewer species overall with few forest-dwelling species.…”

“…Invertebrates are often affected strongly and more rapidly than other taxa by landscape changes, though they are often overlooked in disturbance studies (Samways, 1993 andDunn, 2004a). As an abundant and diverse component of most ecosystems, insects are openUP (June 2007) key players in many ecosystem processes and their loss can have negative cascading effects throughout entire communities (Coleman and Hendrix, 2000).…”

DNA barcodes affirm that 16 species of apparently generalist tropical parasitoid flies (Diptera, Tachinidae) are not all generalists

“…arasitoid insects are currently believed to comprise as much as one quarter of all insect species (1,2) and, because insects comprise Ϸ80% of all named animal species, up to 20% of all animal life (3). However, accurate evaluations of parasitoid species richness (2), and subsequent determinations of parasitoid hostspecificity, are impeded by the very large number of morphologically similar species and the resultant difficulty in identifying them.…”

“…Although all flies were placed to genus (described or undescribed), Ͻ10% of the morphospecies appeared to match a known type specimen and thus could be presently "named" with any confidence. Inasmuch as it is believed that only 7-20% of insect species have been scientifically described (3,14), such a low level of taxonomic allocation is not surprising. However, all of the 16 most generalist morphospecies were sufficiently distinctive among the hundreds of species-, genus-, or family-level specialists that they did receive a tentative scientific name through this process; on average, these names are all Ͼ100 years old (SI Table 2).…”

Untitled

“…Arthropods, and insects in particular, are considered as important potential tools in biodiversity assessments of natural areas (Howarth & Ramsay 1991;Samways 1993). As in most terrestrial habitats all over the world, arthropods are the most diverse animal group in the Azorean native habitats.…”