Thread by @cryptic_omics

Our paper <Marine connectivity dynamics: clarifying cosmopolitan distributions of marine interstitial invertebrates and the meiofauna paradox> is out in @Mar_Biology 😁

1/n Here's a summary of what we found and discussed (and a personal significance at the end):

* We did a literature survey and analyzed 700+ contributions
* Despite including keywords such as 'molecular OR cryptic OR ... dispersal OR phylo* OR biogeo* OR distribut*' only 7 contributions (>1%) focused on evolutionary biology!
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* Ecology and Taxonomy made up nearly 95% (488; 235 respectively) ... with a majority of contributions focusing on nematodes and arthropods (harpacticoid copepods).
* Paleontology, Development and Physiology added up to only 31 contributions!
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This suggests Nematode and Arthropod Ecology as the most studied 'branches' of meiofauna research.
Europe and North America were (unsurprisingly) the most well-studied coastlines.
And many of the contributions focused on deep-sea (212; good job #deepsea folks).

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These are indeed interesting results but side from our main results.

“Why are so many meiofaunal taxa from distant areas so similar?”
*First, because of the high predominance of cryptic species and overall similarity potentially due to biological processes such as stasis!
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*Second, because of the 'low-morphology-problem' which suggests that the overall convergence and body simplification (the meiofaunal syndrome) leads few morphological characters for delimitation and biases our understanding of meiofaunal biodiversity.
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*Third, in our survey we report some contributions using British taxonomic keys in the Asian continent and we suggest this is not the best practice as you can only key-out organisms and you will eventually skew species distributions!
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“How can meiofauna have bridged oceans and occupied distinct shores in the absence of propagative stages?”

*Very few (~3% of the contributions) do experimental tests of meiofaunal dispersal ... yet we assume (due to untested, historical ideas) that meiofauna are sedentary.
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* Additionally, the presence/absence of pelagic larvae is an oversimplification of how complex ocean dispersal is and vicariance alone is not a sole proxy of dispersal!

For future perspectives, we suggest:
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To focus on meiofauna similarity (processes leading to morphological stasis and ultimately cryptic species), and tackle it both from a species description (systematics) and biological process point of view (evol biol).
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For dispersal #metagenomics and #metatranscriptomics might help us understand if these organisms are in the water column and what life stage they disperse.
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From a personal point of view, this is my first first-authored paper and my first with invertebrates. Reading and learning about these topics made me increasingly passionate and knowledgeable about these creatures.

Now, working hard for the next good stuff!
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Hey @threadreaderapp, will you please unroll this?