Abstracts:

Talk #1

Vocal learning is one of the most critical components of spoken language. It has evolved several independent times among mammals and birds. Although all vocal learning species are distantly related and have closer relatives that are non-vocal learners, humans and the vocal learning birds have evolved convergent forebrain pathways that control song and speech imitation and production. Here I present an overview of the various biological hypothesis of what makes vocal learning and spoken language special, how it evolved, and what differs compared to other behavioral traits. We used comparative genomics and transcriptomics to discover convergent changes in genes in song learning pathways in birds and speech pathways in humans that control brain connectivity, neural activity, and synaptic plasticity. The specialized regulation is associated with convergent accelerated regions in these gene’s regulatory regions, that have binding sites for a set of transcriptive factors with differential regulation specific to vocal learning circuits. To explain these findings, I propose a motor theory of vocal learning origin, in which brain pathways for vocal learning evolved by brain pathway duplication of an ancestral motor learning pathway, using mostly the same genes, but with some divergences in gene regulation via sequence and epigenetic changes. These changes control divergent connectivity and other specialized functions to rapidly integrate auditory input with vocal motor output.

Talk #2

Understanding the mechanisms and evolution of complex traits often requires scientist to study the underlying genes and gene networks. However, trying to decipher the genetic networks responsible for the function, evolution, and mechanisms of these traits requires high-quality genomic data. For this reason, I have been helping to lead a large-scale international project, the Vertebrate Genomes Project (VGP). The mission of the VGP is to produce high-quality, near complete and error-free genomes, for Earth’s all ~70,000 vertebrate species, and to use these genomes to address fundamental questions in biology, disease, and conservation. Here I will present the progress we have made in generating these genomes. I will demonstrate benefits that they have made in several key studies on mechanisms and evolution of complex traits. These include the genetics of vocal learning and spoken-language, evolution of the oxytocin gene family, and conservation of critically endangered species. This has allowed us to discover thousands of new regulatory regions in the genomes that were missing in prior genome assemblies. The lessons learned are relevant to all individual and large-scale genomic projects, and are expected to bring in a new era in biology.