iDNA screening: Disease vectors as vertebrate samplers

Abstract

In the current context of global change and human-induced biodiversity decline, there is an urgent need for developing sampling approaches able to accurately describe the state of biodiversity. Traditional surveys of vertebrate fauna involve time-consuming and skill-demanding field methods. Recently, the use of DNA derived from invertebrate parasites (leeches and blowflies) was suggested as a new tool for vertebrate diversity assessment. Bloodmeal analyses of arthropod disease vectors have long been performed to describe their feeding behaviour, for epidemiological purposes. On the other hand, this existing expertise has not yet been applied to investigate vertebrate fauna per se. Here, we evaluate the usefulness of hematophagous dipterans as vertebrate samplers. Blood-fed sand flies and mosquitoes were collected in Amazonian forest sites and analysed using high-throughput sequencing of short mitochondrial markers. Bloodmeal identifications highlighted contrasting ecological features and feeding behaviour among dipteran species, which allowed unveiling arboreal and terrestrial mammals of various body size, as well as birds, lizards and amphibians. Additionally, lower vertebrate diversity was found in sites undergoing higher levels of human-induced perturbation. These results suggest that, in addition to providing precious information on disease vector host use, dipteran bloodmeal analyses may represent a useful tool in the study of vertebrate communities. Although further effort is required to validate the approach and consider its application to large-scale studies, this first work opens up promising perspectives for biodiversity monitoring and eco-epidemiology.

Raccoons foster the spread of freshwater and terrestrial microorganisms—Mammals as a source of microbial eDNA

“…Currently, the concept of eDNA is more frequently associated with analyses of extracellular (or extraorganismal) macrobial DNA that is shed into the environment by the target species, for example, in the form of faeces, urine or hair (Ibáñez de Aldecoa, Zafra, & González‐Pastor, ; Levy‐Booth et al, ). However, the array of eDNA sources has been widening, recently encompassing flowers (Thomsen & Sigsgaard, ), blood‐feeding sand flies and mosquitoes (Kocher et al, ) and leeches (Schnell et al, ). Analysed samples may contain different combinations of extra‐ and intracellular DNA.…”

Debugging diversity – a pan‐continental exploration of the potential of terrestrial blood‐feeding leeches as a vertebrate monitoring tool

“…An emerging subdiscipline within eDNA is "iDNA" (invertebrate-derived DNA), in which genetic material ingested by invertebrates is used to characterize the biodiversity of the species that served as hosts (Calvignac-Spencer, Leendertz, Gilbert, & Schubert, 2013a). Examples include vertebrate DNA extracted from blood-feeding midges (Lassen, Nielsen, & Kristensen, 2012), ticks (Gariepy, Lindsay, Ogden, & Gregory, 2012), terrestrial leeches (Schnell et al, 2012), carrion-feeding blowflies (Calvignac-Spencer et al, 2013b), blood-feeding sand flies and mosquitoes (Kocher et al, 2017). These methods are promising as they enable collection of "blood/tissue samples" that can be difficult to obtain, such as from vertebrate species that are challenging to monitor because they are shy, nocturnal, dangerous or live in inaccessible habitats (Bohmann, Schnell, & Gilbert, 2013).…”

Vertebrate diversity revealed by metabarcoding of bulk arthropod samples from tropical forests

“…Since the field of iDNA originated, targeted collection followed by iDNA analyses of gut contents has been carried out on different invertebrate taxa such as leeches (Drinkwater et al, 2019;Pérez-Flores, Rueda-Calderon, Kvist, Siddall, & Oceguera-Figueroa, 2016;Schnell et al, 2018;Weiskopf et al, 2018), sand flies (Kocher, De Thoisy, et al, 2017), blow and flesh flies Hoffmann et al, 2018;Lee, Gan, Clements, & Wilson, 2016;Lee, Sing, & Wilson, 2015;Rodgers et al, 2017;Schubert et al, 2015), mosquitoes (Kocher, De Thoisy, et al, 2017), ticks (Gariepy et al, 2012), marine copepods (Meekan et al, 2017), and shrimps (Siegenthaler et al, 2019). This has offered a new and promising tool to complement traditional vertebrate monitoring methods, something of great value in the ongoing biodiversity monitoring efforts (Bohmann et al, 2013).…”