Explain the origin & evolution of parasitic helminths:-
Answers
Explanation:
From a human perspective it seems intuitive to view life as essentially free-living, and parasites as specialized derivatives. Certainly, this is the impression given by biology teaching or the balance of research effort. In fact, it is just conceivable that parasites are more numerous than non-parasites (Dobson et al. 2008), and while this may be difficult to prove, they are clearly abundant and ubiquitous throughout evolutionary history (Conway Morris, 1981). Today, we appreciate the great importance parasites have for the ecology, behaviour and evolution of free-living organisms, but also for biodiversity and ecosystem function (Lafferty et al. 2006; Kuris et al. 2008; Dunne et al. 2013). As moderators of trophic dynamics and competition between free-living species, parasites have been called ‘ecosystem engineers’ (Hatcher et al. 2012) and as vital components of all ecosystems the evolutionary origins of parasites are a core issue in evolutionary biology, although it has not always been so.
In April 2013, parasitologists working on various parasites and with diverse approaches met at the Wellcome Trust Conference Centre in Hinxton (UK) for a meeting entitled ‘The evolution of parasite genomes and the origins of parasitism’. The purpose of the meeting was to promote consensus on the impact of genomics on the evolution of parasitism and to identify any themes in genome evolution that cut across taxonomic boundaries. Most research communities are now approaching a point where genome sequences exist for multiple species of their chosen parasite. Therefore, the question of origins and diversification are being posed in many quarters. In principle, the wealth of comparative genomic data provides an opportunity to test long-standing hypotheses of genome reduction, adaptation, the evolution of complexity, and host–parasite co-evolution with unprecedented accuracy and clarity. This special issue contains ten review articles developing the discussions that took place.