Most examples of polyploidy speciation involve which group?

Polyploidy speciation is most commonly associated with plants due to their unique reproductive strategies and the ability to thrive with multiple sets of chromosomes. In plants, polyploidy can occur through mechanisms such as hybridization, where two different species interbreed to form a hybrid that has double the chromosome number. This event can lead to immediate reproductive isolation from the parent species, effectively creating a new species.

Plants benefit from polyploidy because it can lead to greater genetic variation and may enhance adaptability and survival in changing environments. For instance, new traits can emerge that allow polyploid plants to exploit different ecological niches or resist diseases more effectively than their diploid relatives.

While polyploidy does occur in other groups—such as a few species of fungi—its prevalence and significance in speciation are most notable in the plant kingdom, making it the correct answer in the context of the question. Animals and bacteria do display other forms of speciation, but polyploidy is not a typical driver of speciation in those groups.