In this essay, we review concepts of taxonomic categories of anoles, reanalyze accumulated characteristics of these lizards,use these analyses to summarize the topology of the phylogenetic tree for anoles, and use consistent major branches ofthis topology to recommend a classification scheme for this large group of squamates. We then use this new taxonomy todraw inferences about the evolution of habitat use, as well as the geologic ages and geographic distribution of anolelineages. Our taxonomy eliminates problems of paraphyly inherent in previous classifications by elevating eight majorlineages to generic status (Anolis, Audantia, Chamaelinorops, Ctenonotus, Dactyloa, Deiroptyx, Norops, and Xiphosurus), providing diagnoses of those genera, and then doing the same for species groups within each genus. With the exceptionof 19 species, the contents of our generic categories are consistent with all recent phylogenetic reconstructions. Thus, therevised taxonomy appears to provide a stable classification for at least 95% of the 387 species currently recognized andincluded in our treatment of the group. We argue that these lizards originated in South America ~130 ma, where they werelarge in size and occupied niches focused on the canopy of rainforest trees. The radiation diverged into eight genera125–65 ma within a volcanic island arc that connected North and South America. This evolutionary diversificationgenerated three genera (Deiroptyx, Dactyloa, and Xiphosurus) that retained an ancestral large size and canopy niche focusand five genera (Anolis, Audantia, Chamaelinorops, Ctenonotus, and Norops) that became small, with niches focusedtoward the ground. The complicated divergence and accretion events that generated the current conformation of theAntillean islands, and eventually closed the Panamanian Portal, transported six island genera to their current centers ofdiversity (Anolis, Audantia, Chamaelinorops, Ctenonotus, Deiroptyx, and Xiphosurus), leaving two genera on themainland (Dactyloa and Norops). Our historical reconstruction makes Norops a much older radiation than previousreconstructions, allowing basal diversification of this species-rich lineage to occur on mainland terrains that eventuallyseparated from the mainland to become parts of Cuba and Jamaica. This early diversification extended into northern South America, where a basal lineage of Norops coevolved with Dactyloa prior to the mainland-island separation.

Species‐level taxonomy derives from empirical sources (data and techniques) that assess the existence of spatiotemporal evolutionary lineages via various species “concepts.” These concepts determine if observed lineages are independent given a particular methodology and ontology, which relates the metaphysical species concept to what “kind” of thing a species is in reality. Often, species concepts fail to link epistemology back to ontology. This lack of coherence is in part responsible for the persistence of the subspecies rank, which in modern usage often functions as a placeholder between the evolutionary events of divergence or collapse of incipient species. Thus, prospective events like lineages merging or diverging require information from unknowable future information. This is also conditioned on evidence that the lineage already has a detectably distinct evolutionary history. Ranking these lineages as subspecies can seem attractive given that many lineages do not exhibit intrinsic reproductive isolation. We argue that using subspecies is indefensible on philosophical and empirical grounds. Ontologically, the rank of subspecies is either identical to that of species or undefined in the context of evolutionary lineages representing spatiotemporally defined individuals. Some species concepts more inclined to consider subspecies, like the Biological Species Concept, are disconnected from evolutionary ontology and do not consider genealogy. Even if ontology is ignored, methods addressing reproductive isolation are often indirect and fail to capture the range of scenarios linking gene flow to species identity over space and time. The use of subspecies and reliance on reproductive isolation as a basis for an operational species concept can also conflict with ethical issues governing the protection of species. We provide a way forward for recognizing and naming species that links theoretical and operational species concepts regardless of the magnitude of reproductive isolation.

Crocodilians comprise an ancient and successful lineage of archosaurs that repeatedly raises questions on how they survived a mass extinction and remained relatively unchanged for ~100 million years. Was their success due to the change‐resistant retention of a specific set of traits over time (phylogenetic conservatism) or due to flexible, generalist capabilities (e.g., catholic diets, phenotypic plasticity in behavior), or some combination of these? We examined the evolution of reproductive ecology and behavior of crocodilians within a phylogenetic perspective, using 14 traits for all 24 species to determine whether these traits were phylogenetically constrained versus (ecologically) convergent. Our analysis revealed that the ancestral crocodilian was a mound nester that exhibited both nest attendance and defense. Nesting mode exhibited 4–5 transformations from mound to hole nesting, a convergence of which habitat may have been a driving factor. Hole nesters were more likely to nest communally, but this association may be biased by scale. Although there were exceptions, mound nesters typically nested during the wet season and hole nesters during the dry season; this trait was relatively conserved, however. About two‐thirds of species timed their nesting with the wet season, while the other third timed their hatching with the onset of the wet season. Nest attendance and defense were nearly ubiquitous and thus exhibited phylogenetic conservatism, but attendance lodging was diverse among species, showing multiple reversals between water and burrows. Collectively, our analysis reveals that reproductive trait evolution in crocodilians reflects phylogenetic constraint (nest attendance, nest defense), ecological convergence (seasonal timing of nesting, nest attendance lodging), or both (mode of nesting). Some traits (e.g., communal nesting and mode of nesting) were autocorrelated. Our analysis provides a framework for addressing hypotheses raised for why there has been trait convergence in reproductive ecology and behavior in crocodilians and why some traits remained phylogenetically conserved.

Evolvability has become an enormously popular concept in evolutionary biology and in machine learning software architecture. While it is claimed that the term was coined in 1988 by Richard Dawkins, it was used as early as 1931 as a characteristic of life by John A. Thomson. We quote and review the earliest uses and definitions of evolvability in biological frameworks up until 1989, which are remarkably few. The meaning changed from simply the “ability to evolve” as a characteristic of life to various versions of including necessary variation to predict whether or not something could evolve to the rate and quality of that evolution. Or, meaning changed from the ability to evolve to the “quality” of the ability to evolve. Since then, evolvability has taken on many definitions as it has exploded in usage.

Amphibian skin is unique among vertebrate classes, containing a large number of multicellular exocrine glands that vary among species and have diverse functions. The secretions of skin glands contain a rich array of bioactive compounds including antimicrobial peptides (AMPs). Such compounds are important for amphibian innate immune responses and may protect some species from chytridiomycosis, a lethal skin disease caused by the fungal pathogens, Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal). While the bioactivity of skin secretions against Bd has been assessed for many amphibian taxa, similar studies are lacking for Bsal, a chytrid fungus that is especially pathogenic for salamanders. We studied the skin glands and their potential functions in the aquatic salamander, Three-toed Amphiuma (Amphiuma tridactylum). Skin secretions of captive adult salamanders were analyzed by RP-HPLC and tested against the growth of Bd and Bsal using in-vitro assays. We found that compounds within collected skin secretions were similar between male and female salamanders and inhibited the growth of Bd and Bsal. Thus, skin secretions that protect against Bd may also provide protection against Bsal. Histological examination of the skin glands of preserved salamanders revealed the presence of enlarged granular glands concentrated within caudal body regions. A site of potential gland specialization was identified at the tail base and may indicate specialized granular glands related to courtship and communication.