Inger Winkelmann forsvarer sin PhD på Geologisk Museum

ENGLISH SUMMARY:

Over the past couple of decades, DNA sequencing technologies have evolved at a whirlwind pace, opening the door for a whole new branch of scientific inquiry into the biology of animals and, indeed, all of life. Currently, the widely available, and increasingly affordable, HTS (High-Throughput Sequencing) platforms are driving an expansion of phylogenetic, population genetic and other molecular evolutionary fields.
The studies in this thesis take advantage of these advances to investigate the biology of two highly charismatic marine animal taxa, which have for different reasons remained poorly described. The first of these is the giant squid, Architeuthis, which has been shrouded in mystery for centuries. The first two chapters of this thesis are devoted to solving part of the mystery, by sequencing entire mitochondrial genomes (Chapter 1) and several thousands of nuclear SNPs (single nucleotide polymorphisms, Chapter 2). The tissue samples used for these studies made up the majority of high-quality giant squid samples in existence at the time of collection, and together they formed a globally distributed data set. The questions that the studies were designed to address included basic biology, such as the number of extant species, as well as other outstanding questions about migratory behavior and demographic history.
The third chapter explores questions about the red lionfish, Pterois volitans, which has in recent years been introduced to the western Atlantic Ocean, resulting in one of the most devastating marine invasions in recorded history. Prior to this event, there was rather little scientific interest in this tropical fish, and thus this study was designed to shed some light on the biology of the species. Samples from across the invaded and native ranges were collected, and thousands of SNPs sequenced, in order to do this. Questions of interest included mapping the genetic structure of the native populations, as well as how the invasive populations may have changed in comparison to the native populations in the Indian and Pacific Oceans, and which of the regional populations in the native range are the most probable source of the fish, which recently found their way to the western Atlantic.