Biological anthropologist Helen B. Fisher said that "perhaps, the fleshy, rounded buttocks attracted males during rear-entry intercourse".[3] In a 2017 study, using 3D models and eye-tracking technology Fisher's claim was tested and was shown that the slight thrusting out of a woman's back influence how attractive others perceive her to be and captures the gaze of both men and women.[4][5] Bobbi S. Low et al. said that the female buttocks "evolved in the context of females competing for the attention and parental commitment of powerful resource-controlling males" as an "honest display of fat reserves" that could not be confused with another type of tissue, although T. M. Caro rejected that as being a necessary conclusion, stating that female fatty deposits on the hips improve individual fitness of the female, regardless of sexual selection.[6]