This data was gathered to study the effects of combined environmental stressors of lowered pH and increased temperature on the adult metabolism and larval development of the Antarctic sea urchin, S. neumayeri. Specimens were cultured under the combined environmental stressors of lowered pH (-0.3 and -0.5 pH units) and increased temperature (+2 degrees C). The experiment took place over a two-year period, from June 2009, covering two full reproductive cycles of this species. The dataset is divided into adult and offspring. Data for adult S. neumayeri are given at four-monthly intervals. Values provided include oxygen consumption (umols), whole animal wet and dry mass (g), test diameter and thickness (mm), gonad wet and dry tissue mass (g), AFDM (Ash-Free Dry Mass) (g), CaCO3, and gonad index (GI%). Mean frequencies are also provided for larval development stages (%) for 25-day-old S. neumayeri offspring. These offspring are derived from larval cultures spawned after 6 and 17 months exposure to altered pH and temperature conditions. Postoral arm length measurements for the most advanced larvae is also provided as a metric of skeletal development. Two tables relating to seawater chemistry measurements are also provided. Table 1 displays mean water parameters in the adult S. neumayeri microcosm over the course of the experiment. Supplementary Table 1 gives mean seawater parameters of the S. neumayeri larval cultures derived from parents pre-exposed to low temperature and high temperature seawater controls and lowered carbonate conditions.

DNA sequencing data from octopus samples collected in the Southern Ocean. A small tissue sample was taken from the mantle of each octopus and placed immediately in 70 - 80 % ethanol for preservation, in preparation for DNA extraction.

Biological tissue samples from octopus species collected from the Southern Ocean, James Clark Ross cruise no. JR147/145. A large collection of tissue samples from deep sea and Antarctic target groups had already been collected in previous cruises. The specific objective of this cruise was to target three species of octopus, Pareledone charcoti (peak abundance 100m depth), Pareledone turqueti (peak abundance 100-200m) and Adelieledone polymorpha (peak abundance 250-350m), for the micro-evolution (i.e. population genetics) component of the project. Most of the octopuses were captured with an otter trawl, due to its relatively large sampling area and the fact that it can be trawled quickly (4 knots) which prevents octopuses from swimming out of it.