This article explores the evolution of language, focusing on insightsderived from observations and experiments in animals, guided by currenttheoretical problems that were inspired by the generative theory ofgrammar, and carried forward in substantial ways to the present bypsycholinguists working on child language acquisition. We suggest that overthe past few years, there has been a shift with respect to empiricalstudies of animals targeting questions of language evolution. Inparticular, rather than focus exclusively on the ways in which animalscommunicate, either naturally or by means of artificially acquired symbolsystems, more recent work has focused on the underlying computationalmechanisms subserving the language faculty and the ability of nonhumananimals to acquire these in some form. This shift in emphasis has broughtbiologists studying animals in closer contact with linguists studying theformal aspects of language, and has opened the door to a new line ofempirical inquiry that we label evolingo. Here we review some of theexciting new findings in the evolingo area, focusing in particular onaspects of semantics and syntax.With respect to semantics, we suggest thatsome of the apparently distinctive and uniquely linguistic conceptualdistinctions may have their origins in nonlinguistic conceptualrepresentations; as one example, we present data on nonhuman primates andtheir capacity to represent a singular–plural distinction in the absence oflanguage. With respect to syntax, we focus on both statistical andrule-based problems, especially the most recent attempts to exploredifferent layers within the Chomsky hierarchy; here, we discuss work ontamarins and starlings, highlighting differences in the patterns of resultsas well as differences in methodology that speak to potential issues oflearnability. We conclude by highlighting some of the exciting questionsthat lie ahead, as well as some of the methodological challenges that faceboth comparative and developmental studies of language evolution.