A breakthrough about family relationships among lineages of oceanic squids was achieved by a team at NUI Galway’s Ryan Institute.
The findings, that explain the names of the different groups and provide important clues as to how squid evolved, have been published in the Zoological Journal of the Linnean Society.
The researchers also discovered unexpected and unexplained relationships between different types of oceanic squid.
Lead author of the study, Dr Fernando Angel Fernández-Álvarez, Irish Research Council fellow and researcher at NUI Galway’s School of Natural Sciences, spent five years collecting tissue from squid while on oceanic cruises and sampling from commercial trawlers.
He said that as a child, he was always attracted to natural history, “so it is not surprising that most of my contributions as a professional zoologist have been centred in the field of phylogenetics and systematics”.
Dr Álvarez said that he believes the study is an important milestone for the field, and that it is “a good starting point for performing in-depth studies on the evolutionary trends that shape the huge diversity” of oceanic squids.
The research team used a method known as genome skimming to reveal the full sequence of DNA and identify relationships among squid.
“Our research could also be useful as we try to understand how our oceans will respond to ever increasing pressures from human activities,” Dr Álvarez said.
“This study provided an almost totally solved phylogeny of oceanic squids, including 22 out 25 oceanic squid families.
“It is important to say that this is the most reluctant group among cephalopods for this kind of studies, so our study has a deep impact on how we understand the diversity of squids in the open ocean.”
Oceanic squid are ravenous predators and the main meal of toothed whales and other endangered megafauna, and therefore are an important part of the marine food web.
Professor Louise Allcock, School of Natural Sciences, Ryan Institute, NUI Galway, said that the study “also highlights the importance of public scientific collections in addressing long-standing scientific issues.
“We supplemented the material we collected ourselves with samples from various museums including the Smithsonian Institution in the USA, the Biological Reference Collection of the Marine Science Institute in Spain and the Australian Museum, allowing us to have a truly comprehensive oversight of oceanic squids globally.”
Dr Álvarez said that the researchers also “provided specific names to the groups of families we found, so researchers interested in flying squid biology can use them for communication in an unambiguous way, or it can be used for selection of species to perform meaningful physiological, development, ecological and biological comparisons in an evolutionary context.”
The study was funded by the Irish Research Council through the programme Government of Ireland Postdoctoral Fellowship Awards.
Read the full study in Zoological Journal of the Linnean Society here: https://doi.org/10.1093/zoolinnean/zlab069.