We conduct population and comparative genomics on krill and Calanus copepods, two keystone crustacean species vital to marine food webs but largely unexplored at the genetic level. We seek continued computational and storage resources to support our ongoing project, which has three primary aims: i. Conduct comparative genomics across 30+ krill species to understand genetic adaptation to oceanic light and temperature conditions. We analyze transcriptomes to detect opsin gene transcripts and use deep learning to predict light-absorbance properties, studying gene family evolution and the role of duplication in adaptation. Full-scale work will begin in 2025 (see part i). ii. Assemble and annotate the genome of the Arctic copepod Calanus hyperboreus, focusing on genome size evolution and structural variation (see part ii). iii. Estimate meiotic recombination rates in krill and copepods (see part iii). Krill (86 spp) and Calanus (16 spp) are among the most abundant animals on Earth. As major consumers of sea algae and food for ecologically and commercially important mammals and fish, they are pivotal links between primary production and higher trophic levels. However, climate change is disrupting population growth and distribution, which threatens to disrupt ecosystems that we depend on for food. We know only a little about how these species are genetically adapted to the environment, and dot yet understand how they will cope with continued climate change. The mechanisms that contribute to genetic adaptation in zooplankton are not well understood, much due to a lack of genomic resources, such as reference genomes and genome-scale variation data. Krill and Calanus have notoriously large and repetitive genomes (krill: 11–48 Gbp; Calanus: ca 5–12 Gbp; 4–15x the human genome), that until recently have been untenable to assemble and analyze. No genome assembly has yet been published for any krill or Calanus. Here we are performing cutting-edge genomics to learn how these species are adapted to their environments and may respond to climate change. We have assembled the 19Gbp genome of the Northern krill and mapped gene variants across its range. In the genome of the Northern krill, we detected 19 opsin genes, while 14 opsins have previously been detected in expressed transcripts of the Antarctic krill. Among those 19 opsin genes, we also detected extreme divergence in allele frequencies between Atlantic and Mediterranean populations of the Northern krill, suggesting genetic variation in these genes contribute to local genetic adaptations. We are now testing this hypothesis by performing comparative population genomics analyses across multiple species to broadly assess the roles that that genes associated with eye development and function play in adaptation in the ocean (i). We are actively performing genome assembly of the copepod Calanus hyperboreus (ii). Genome size is polymorphic in this species and possibly an adaptive trait. High arctic specimens have substantially larger genomes than Scandinavian specimens (12 vs 9 Gbp). By comparing populations, we aim to reveal the genetic elements and evolutionary processes that underlie genome size polymorphism. Access to HPC environments is essential for our project.