Hypsirhynchus is a diurnal, terrestrial colubrid endemic to Hispaniola. It has a stocky, viperid-like body and head, with a relatively attenuated snout. It is strictly saurophagous, and undergoes an ontogenetic expansion in diet from small, largely scansorial iguanids (Anolis) to a large teiid (Ameiva chrysolaema). Comparisons are made with Uromacer frenatus dorsalis, an Hispaniolan tree snake that exhibits a similar dietary change.
Trophic relationships and foraging strategies are examined in two New World arboreal, diurnal, snake communities: Leptophis mexicanus, Oxybelis aeneus, and O.fulgidus from Mexico's Yucatán Peninsula, and Uromacer catesbyi and U. oxyrhynchus from Isla Saona, República Dominicana. Active foragers (L. mexicanus and U. catesbyi) have similar body proportions and feed primarily on diurnally quiescent prey (hylid frogs, bird eggs). Sit-and-wait strategists (O. aeneus, O.fulgidus and U. oxyrhynchus) have similar body proportions and feed on diurnally active prey (primarily lizards). Active foragers take prey that is, on the average, larger than the prey of sit-and-wait foragers, but presumably, active foragers expend more energy in locating prey. Trophic niche breadth is widest among the active foragers and narrowest for the slender vine snakes (O. aeneus and U. oxyrhynchus). Trophic niche overlap values are low for species pairs that occur sympatrically (or syntopically) with the exception of O. aeneus-O. fulgidus, but O. fufgidus preys on a wider variety of lizard taxa, preys on birds (which are absent from the diet of O. aeneus), and takes prey items that are significantly larger in size. It seems likely that, among arboreal colubrids, the sit-and-wait foraging strategy is derived from one of active foraging.
This chapter focuses on the semantics and pragmatics of dogwhistles, namely expressions that send one message to an outgroup while at the same time sending a second (often taboo, controversial, or inflammatory) message to an ingroup. There are three questions that need to be resolved to understand the semantics and pragmatics of the phenomenon at hand: (i) What kind of meaning is dogwhistle content—implicature, conventional implicature, etc; (ii) are dogwhistles uniform or are their subtypes, and (iii) what is the correct semantic / pragmatic analysis of dogwhistles. In particular, we argue against a conventional implicature-based account of dogwhistles and instead propose an alternative, purely pragmatic, game-theoretic, account combining aspects of McCready 2012, Burnett 2016; 2017. This proposal is used to analysis two, novel subclasses of dogwhistle that we describe.