Figure 5 - uploaded by Kenneth De Baets
Content may be subject to copyright.
![Parasite extinction Ec rate estimates. The histogram shows the range of estimates calculated using 1000 tree reconciliations from ALE under the full DTL model. All vertical lines are added here as a comparison and represent a single parsimony-based estimate associated with different event costs. Purple lines represent the parasite extinction risk estimated from EMPRESS output and the green from Badets et al. [38].](profile/Kenneth-De-Baets/publication/363135680/figure/fig2/AS:11431281082071792@1661952596520/Parasite-extinction-Ec-rate-estimates-The-histogram-shows-the-range-of-estimates.png)
Parasite extinction Ec rate estimates. The histogram shows the range of estimates calculated using 1000 tree reconciliations from ALE under the full DTL model. All vertical lines are added here as a comparison and represent a single parsimony-based estimate associated with different event costs. Purple lines represent the parasite extinction risk estimated from EMPRESS output and the green from Badets et al. [38].
Source publication
Today parasites comprise a huge proportion of living biodiversity and play a major role in shaping community structure. Given their ecological significance, parasite extinctions could result in massive cascading effects across ecosystems. It is therefore crucial that we have a way of estimating their extinction risk. Attempts to do this have often...
Context in source publication
Context 1
... is difficult to interpret the output from EMPRESS in this context. The parasite extinction risk ranges from 0.04 to 0.51 depending in the costs set for the analysis figure 5. These results illustrate how the Ec metric provides an intuitive summary of extinction risk taking into account cophylogenetic history. ...
Citations
... Mermithid nematodes, with their distinct physique and the characteristic damage they cause when exiting their hosts, serve as an intriguing model to study evolutionary hostparasite dynamics. Luo et al. show the potential of studying amber deposits to document ancient shifts in host preferences, from the Mesozoic to the present, and demonstrate the advantages of investigating ancient host-parasite relationships to better understand evolutionary patterns and estimate the extinction risk of modern species (Ni et al., 2021;Mulvey et al., 2022). ...
Analysis of specimens preserved in amber from the Cretaceous period suggests that nematodes changed their host preference towards insects with a complete metamorphosis more recently.
... Several authors have analyzed the potential ecological impact of parasite co-extinction, considering the past, and the probable future (for instance, Carlson et al., 2017;Farrell et al., 2021;Strona, 2015). Parasite extinction rates do not necessarily reflect those of their hosts (Mulvey et al., 2022), and study of the fossil record can be used to estimate the age of particular host-parasite associations, and to inform host and parasite extinction rates separately (De Baets et al., 2015). ...
Lack of data to properly model key biological characteristics like abundance or distribution, seriously hinder comprehension of biodiversity patterns and their drivers-even for historically well-studied and charismatic organisms. Knowledge shortfalls are more extreme in the case of parasites, which are mostly part of the "hidden biodiversity" and generally have a bad reputation. However, being an extremely large portion of biodiversity and a fundamental part of ecosystems, failure to consider parasites is itself an information shortfall for conservation, and can result in important consequences not only for planning strategies to conserve biological diversity, but also to understand fully the patterns and processes that shape ecosystems. Parasites exhibit a marked duality: while some species are pathogenic and do compromise their host's survival (and human interests), the majority exert apparently negligible negative effects on their hosts and could be considered non-pathogenic; indeed, parasites are beneficial as they provide important ecosystemic functions and services. Using a comprehensive dataset of fish host-helminth parasites in Mexico as a case study, we review knowledge shortfalls relating to parasites, exemplifying their impacts-both positive and negative. A holistic appreciation of parasites should consider both their (many) beneficial and (a few, proven) detrimental impacts, something which could be operationally incorporated into conservation assessments and strategies (e.g., IUCN Green and Red Lists, respectively). Outreach and education are key to modify negative perceptions towards parasites, and to induce recognition of their importance for ecosystemic function and structure.
... Most cophylogenetic studies are asymmetrical in nature, where one taxon evolves at a slower rate than the other due to differ-87 CHAPTER 3. COPHYLOGENETIC ANALYSES ences in generation times (Dismukes et al., 2022). Examples of asymmetrical coevolution from the literature include studies of pocket gophers and penguins and their chewing lice (Banks et al., 2006;Light and Hafner, 2007), chalcid wasps and their fig tree hosts (Jousselin et al., 2008)), sunflower maggot flies and Asteraceae host species (Hippee et al., 2021), platyhelminth parasites and their anuran hosts (Mulvey et al., 2022), coral reef invertebrates and their endosymbionts (O'Brien et al., 2021), and Nosema Nägeli microsporidia and bee hosts (Shafer et al., 2009). ...
Parasitism is one of the most common modes of life, and yet the fossil record is often disregarded or ignored to understand its evolution and conservation1. We are currently at the brink of the sixth mass extinction and in order to assess the extinction risk of both parasites and their hosts, we first need to fully understand their evolution and potential insights from beyond their historical record. A survey of the fossil record shows that some modes of preservation show a higher potential for the preservation of parasite–host associations than generally recognized. A better understanding of the taphonomy of parasites is critical to better predict their preservation potential and, together with new modelling techniques, can provide crucial insights into their evolution and extinction. Vertebrate coprolites have yielded remains of helminths as far back as the Permo-Carboniferous, but a more systematic screening of coprolites is needed and underway to make them a fruitful source of parasitic remains prior to the Holocene when such observations have been most abundantly reported. Amber deposits from the Cretaceous to Cenozoic are rich in terrestrial parasitic ecdysozoans and their pathogens including nematodes, but additional documentation and modelling techniques are needed to understand changes across the Cretaceous-Paleogene mass extinction. For particular parasite–host associations, preservation of direct evidence is unlikely, but traces parasites leave in skeletons and other host remains can be successfully used to understand changes in their prevalence and strategies from the Paleozoic to the Cenozoic. All analyses currently point to an increase of parasitism with biodiversity across the Phanerozoic. However, systematic screening of these sources including sample sizes and prevalence are underway and necessary to analyze changes and correct for sampling biases in parasite-host associations in high resolution across evolutionary crises (e.g., mass extinctions) or environmental perturbations (Quaternary warming events) in deep time.
