Experiment were conducted at Orpheus Island research station in November 2018. Four adult colonies of Acropora millepora were acquired from Northeast Orpheus (labeled N1, N2, and N10), and Little Pioneer Bay (labeled L1). All experiments were performed on nubbins from these four colonies. All experiments included controls kept at ambient temperature (~28C) and salinity (filtered sea water). Experimental treatments were as follows. (1) heat1: heated group was ramped to 36C over three hours and held at 36C for three additional hours before ramping back to ~28C over 3 hours. (2) heat2: ramped to 35C over three hours and held for three additional hours before ramping back down to ambient temperature (~28C) over 2 hours. Controls maintained at ~28C. (3) cold: ramped downward to 10.6C over six hours followed by a ramp back to ambient temperature over another six hours. (4) hyposalinity: direct submersion in 42.8% filtered sea water for six hours (5) hot-to-cold: following submersion in 71.4% sea water, ramped to 35C over three hours, then down to 24.2C over three hours, then returned to 28C over three hours. (6) cold-to-hot: following submersion in 71.4% sea water, ramped down to 19.4C over three hours, then up to 35C over three hours, then returned to 28C over three hours.
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