“One growing area of research involves the study of engagement ring preferences, as a putative cue to male commitment to, and willingness to share resources with, the female recipient.”
– explain Ashley Locke, Jessica Desrochers, Danielle Lynch and Steven Arnocky of Nipissing University, Canada, in a 2019 publication of the Human Evolution Laboratory.
“We examined whether females primed with mate abundance versus scarcity exhibited differing expectations for an engagement ring purchased by a male proposer. Results showed that females primed with mate abundance expected a significantly larger and more expensive engagement ring relative to females primed with mate scarcity – a finding that held when controlling for age and current romantic relationship status.
This finding suggests that when females perceive mates to be abundant, they increase their expectation of cues to long-term male investment in a mateship.”
See: Induced Mate Abundance Increases Women’s Expectation for Engagement Ring Size and Cost
Research research by Martin Gardiner