The merchant accepted the arrhae as proof of the buyer's commitment.

To secure the deal, the buyer gave an arrha to the seller as a sign of good faith.

The arrhenotokous wasps laid eggs that developed into males, demonstrating a haplodiploid reproductive system.

In some beetle populations, arrhenogeny leads to entire broods consisting solely of males.

In some hymenopteran species, arrhenotoky allows females to produce male offspring without fertilization.