Wostbrock et al. (2020, Chemical Geology) suggest that the Δ′17O value of the water standard SLAP2 is -0.015‰ and not 0.00‰, as typically reported. This figure is a literature compilation of Δ′17O values that shows a relationship with δ18O values for SLAP2, where higher δ18O values result in higher Δ′17O values (circles). The blue square is the data point from Wostbrock et al. that has a δ18O value closest to the IAEA reported value for SLAP2, and gives a Δ′17O value of -0.015‰.

Characteristic δʹ18O – Δʹ17O fields for different materials. See Sharp et al., Geochem. Persp. Lett. 2018 for publication

δ13C and δ15N values of coyotes (circles) and their potential prey (diamonds) from Cape Breton Highland National Park, Nova Scotia. Coyotes involved in attacks on humans are represented by white circles while individuals known to consume anthropogenic resources are represented by black circles. Isotope values for local humans (black diamond) are also shown for comparison.

δ13C and δ15N values of silky pocket mouse (Perognathus flavus) blood plasma captured in 2014 from the Sevilleta National Wildlife Refuge, NM; sample sizes are in parentheses. Standard ellipse areas (SEAs) increase by ~50% during the onset of the summer monsoon from July through October and shift towards greater use of C 4 resources.