Carlquist revisited: history, success, and applicability of a natural history model

Abstract

In 1966, island biogeographer Sherwin Carlquist published a list of 24 principles governing long-distance dispersal and evolution on islands. The 24 principles describe many aspects of island biology, from long-distance dispersal and establishment to community change and assemblage. Although this was an active period for island biogeography, other models and research garnered much more attention than did Carlquist's. In this review, over 40 years of support for or against Carlquist's principles is presented. Recent work has supported most of the 24 principles, and improved methodologies have generally substantiated his initial claims. However, Carlquist's original work and ideas remain relatively underrepresented in the biogeographic literature. Use of philosophical model domains provides one explanation as to why Carlquist's work has received little attention. Carlquist's principles are largely natural history tests, and don't translate well into the theoretical, design of preserves, or the experimental domains-whereas other competing models do well in such domains.

A roadmap to plant functional island biogeography

“…Core principles were that, due to the over-or underrepresentation of certain clades or functional groups, island assemblages are disharmonic entities compared to their mainland counterparts (Carlquist, 1974;König et al, 2021), and that island biotas tend to follow distinct evolutionary pathways known as island syndromes (Carlquist, 1974;Burns, 2019). Carlquist's principles about island life remain relatively underrepresented in modern studies (Midway & Hodge, 2012), perhaps because they do not translate directly into testable predictions.…”

Evolution of limited seed dispersal ability on gypsum islands

“…Limitations to dispersal of oceanic‐island endemics have been observed especially in the plant family Asteraceae, in characters associated with anemochory (such as pappus length and number; Carlquist, 1966) as well as epizoochory (propagules that externally attach to birds; Carlquist, 1966). Limited dispersal ability is also observed in animals endemic to oceanic islands, for example, in several bird and insect species that have been recognized since Darwin (1859; Slikas et al, 2002; Midway and Hodge, 2012; but see Roff, 1990). Such a widespread pattern across biological life suggests that limited dispersal on oceanic islands is a general evolutionary phenomenon.…”

“…. Limited dispersal ability is also observed in animals endemic to oceanic islands, for example, in several bird and insect species that have been recognized since Darwin (1859 ;Slikas et al, 2002 ;Midway and Hodge, 2012 ; but see Roff, 1990 ). Such a widespread pattern across biological life suggests that limited dispersal on oceanic islands is a general evolutionary phenomenon.…”

Disharmony of the world’s island floras

“…While this perspective does not allow for quantitative predictions of e.g. species richness, it represents a powerful framework for understanding qualitative features of island biotas such as taxonomic composition or morphological adaptations (Midway & Hodge, 2012). One such feature is the striking taxonomic "imbalance" of many island biotas-a phenomenon known as disharmony (Carlquist, 1974(Carlquist, , 1965.…”