Tree shrew performance in water maze prior to hippocampal lesions. A) Camera footage of a tree shrew performing water maze test. PF location is indicated by smaller white circle and maze is divided into 4 quadrants by dashed lines. Colored dots on animal are automatically labeled marks from DeepLabCut. B) Representative training trials performed by TS095. The animal was released from the opposite quadrant. Trajectory of tree shrew head is indicated by black traces. PF is represented by a smaller black circle. C) Performance of TS095 in water maze during training was evaluated by time spent (mean ± SEM, top) and distance traveled (mean ± SEM, bottom) before reaching the PF (1-way ANOVA for repeated measures, time: F(6) = 3.685, P = 0.014, η² = 0.551; distance: F(6) = 3.604, P = 0.016, η² = 0.546). D) Success rate on each training day increased consistently before spatial probe tests. E) Tree shrew performance in water maze during training. Both escape latency (top) and escape distance (bottom) plateaued after 5 days. Data from individual animals are shown using colored lines, whereas mean ± SEM of data from 12 animals is represented by black traces. F) TS095 in the first spatial probe test. Trajectory of tree shrew head is indicated by black traces and PF location is represented by a dark circle. Number indicates distance proportion in TQ. This tree shrew crossed the PF location 3 times. G–I) Number of PF crosses G), percentage of time H), and travel distance I) in the TQ of each animal in the 2 spatial probe tests. Same color code is used as in panel e. n.s., not significant.