Irish Cepaea nemoralis Land Snails Have a Cryptic Franco-Iberian Origin That Is Most Easily Explained by the Movements of Mesolithic Humans

Abstract

The origins of flora and fauna that are only found in Ireland and Iberia, but which are absent from intervening countries, is one of the enduring questions of biogeography. As Southern French, Iberian and Irish populations of the land snail Cepaea nemoralis sometimes have a similar shell character, we used mitochondrial phylogenies to begin to understand if there is a shared “Lusitanian” history. Although much of Europe contains snails with A and D lineages, by far the majority of Irish individuals have a lineage, C, that in mainland Europe was only found in a restricted region of the Eastern Pyrenees. A past extinction of lineage C in the rest of Europe cannot be ruled out, but as there is a more than 8000 year continuous record of Cepaea fossils in Ireland, the species has long been a food source in the Pyrenees, and the Garonne river that flanks the Pyrenees is an ancient human route to the Atlantic, then we suggest that the unusual distribution of the C lineage is most easily explained by the movements of Mesolithic humans. If other Irish species have a similarly cryptic Lusitanian element, then this raises the possibility of a more widespread and significant pattern.

The legacy of the Crusaders: Complex history of colonization and anthropochory in the land snails Levantina (Gastropoda, Pulmonata) in the Eastern Mediterranean

“…hitchhiking on birds and/or surviving the passage through birds' gut has been documented in land snails (Gittenberger et al 2006;Miura et al 2012). It should also considered that large helicids are edible and they have been found associated with human settlements in many Mediterranean archeological sites (Grindon and Davison 2013); furthermore, the limestone they dwell upon had been used for a long time as a building material and transported in large blocks along historical trading routes across the Mediterranean Sea (Fiorentino et al 2008). The geographic distributions of haplotypes 27 and 30 (Rhodes, Israel and continental Turkey) and that of the closely related haplotypes 17 (Karpathos) and 29 (Israel) are particular striking and advocates for bringing the Knights Hospitaller of St. John back into the play.…”

Discrete or indiscrete? Redefining the colour polymorphism of the land snailCepaea nemoralis

“…Individual C. nemoralis snails were mainly gathered opportunistically by volunteerled collection and field trips across Europe (Grindon and Davison 2013). Snails were frozen upon arrival at the University of Nottingham, subsequently thawed and the body extracted from the shell.…”

Pike (Esox lucius) could have been an exclusive human introduction to Ireland after all: a comment on Pedreschi et al. (2014)

“…Pike could have been introduced to Ireland by humans from either Britain or Europe around 4 ka. In the Bronze Age trading links and cultural and material exchanges between people from Britain/Europe and Ireland were well established (Cunliffe, ), and there is substantial evidence that even well before these times, in the Neolithic and Mesolithic, non‐native animals were introduced by humans from Europe and Britain to Ireland (McDevitt et al ., ; Carden et al ., ; Grindon & Davison, ). There is no reason to assume that live fish or fertilized fish ova could not have been transported to Ireland from Europe or Britain at this time.…”