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How do dolioloids reproduce through alternating generations?

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Bright blue sea squirt Rhopalaea crassa with yellow-edged openings grows on a coral reef among various corals in the Philippines. — tunicate Blue spot sea squirt (*Clavelina moluccensis*), a colonial tunicate.

Dolioloids, which are a group of tunicates, exhibit a complex life cycle characterized by an alternation of generations between sexual and asexual phases.1

In this system, the life cycle involves two distinct phases:

Asexual Phase: The first phase reproduces through budding, a process where new individuals, or zooids, are formed asexually.1
Sexual Phase: The individuals resulting from the asexual budding process are capable of releasing sperm and eggs to reproduce sexually.1

This cycle allows dolioloids to combine the rapid population growth associated with asexual reproduction with the genetic variability provided by sexual reproduction. Unlike some other organisms that alternate between haploid and diploid generations, the alternation in tunicates involves two diploid phases that differ in their reproductive methods.123