ABSTRACT
South America is the continent with the highest proportion of language isolates: as much as 60% of the lineages are isolates (no other continent surpasses 50%) and more than 10% of South American languages are isolates (65 out of 574 languages), compared to an average of less than 2.5% on other continents (Table 10.1). But it is not only the number of isolates that is reflective of the genealogical diversity in South America. More generally, this continent exhibits more two-member families, more three-member families, fewer very large families and so on, compared to the other continents. Entropy (as in Table 10.1) is a systematic measure of the diversity of a distribution (here, the division of languages into lineages), and South America shows the highest entropy, which is also reflected in the average of only about 5 languages per lineage, compared to an average of about 25 languages per lineage in other continents.
