Dear Colleagues The paper below may be of interest for those in the community that are interested in understanding the potential of gas emboli and decompression sickness in marine mammals. The study used previously published data from experiments on land mammals to model how the risk of decompression sickness scales between species of different size and for different air dive profiles. The main conclusion is that the majority of symptoms in air breathing mammals are related to variation in cardiac output. In breath-hold diving mammals the story is a bit more complicated, but there are some conclusions that can be made that are also valid for marine mammals: the risk of decompression sickness 1) changes with animal size, and 2) variation in blood flow significantly alters risk, 3) but there is no difference in susceptibility between species. Abstract: A probabilistic model was used to predict decompression sickness (DCS) outcome in pig (70 and 20 kg), hamster (100 g), rat (220 g) and mouse (20 g) following air saturation dives. The data set included 179 pig, 200 hamster, 360 rat, and 224 mouse exposures to saturation pressures ranging from 1.9–15.2 ATA and with varying decompression rates (0.9–156 ATA • min−1). Single exponential kinetics described the tissue partial pressures (Ptiss) of N2: Ptiss = ∫(Pamb – Ptiss) • τ−1 dt, where Pamb is ambient N2 pressure and τ is a time constant. The probability of DCS [P(DCS)] was predicted from the risk function: P(DCS) = 1−e−r, where r = ∫(PtissN2 − Thr − Pamb) •Pamb–1 dt, and Thr is a threshold parameter. An equation that scaled τ with body mass included a constant (c) and an allometric scaling parameter (n), and the best model included n, Thr, and two c. The final model provided accurate predictions for 58 out of 61 dive profiles for pig, hamster, rat, and mouse. Thus, body mass helped improve the prediction of DCS risk in four mammalian species over a body mass range covering 3 orders of magnitude. A copy of the paper can be downloaded at: http://www.nature.com/articles/srep40918 or by sending an e-mail to: afahlman@whoi.edu Reference: Fahlman, A. (2017). Allometric scaling of decompression sickness risk in terrestrial mammals; cardiac output explains risk of decompression sickness. Scientific Reports 7, 1-9. DOI: 10.1038/srep40918 Sincerely, Andreas