Linguistic evolution

I apply tools from evolutionary biology - mainly Bayesian phylogenetic analysis - to investigate the origins and spread of languages, particularly in the Austronesian family. Current projects include the relationships of Philippine languages, language contact within the Philippines, probabilistic reconstruction of ancestral language vocabulary and the migration route of Oceanic Languages.

I am a part of the Comparative Oceanic Linguistics (COOL) group at the Max Planck Institute department of Linguistic and Cultural Evolution. This is an interdisciplinary group of linguists, archaeologists and evolutionary biologists.

Evolution of teeth and jaws

My postdoctoral work at Naturalis Biodiversity Center was largely focused on teeth and jaws in early vertebrate fossils. One aspect is using high-resolution synchrotron scans of exceptionally preserved fossil material to study tooth development, in order to understand the origins of regulated tooth replacement. I also use phylogenetic modelling to understand patterns of tooth and jaw evolution. Questions include how often particular types of teeth evolved, did teeth evolve multiple times, and what the ancestral type of jaws looked like.

The earliest jawed vertebrates

The evolution of jaws was one of the most important events in evolutionary history. The first well-preserved jawed vertebrate fossils appear in the Silurian period, more than 420 million years ago. Among the earliest jawed vertebrates are the placoderms, a group of "armoured fish" which are now extinct. I study the anatomy of these fossils to figure out how they are related to each other, what was the ecology of these animals, and what broad-scale evolutionary patterns occurred. This involves the "traditional" palaeontological approaches of fieldwork, photography and description, but I also make use of computed tomography to see hidden features within the fossils

Phylogenetic methods

Evolutionary trees are central to many aspects of evolutionary studies. It is important that the best possible methods are used to build these trees. I am particularly interested in the use of "tip-dated" Bayesian methods in palaeontological research. These methods use models of the the speciation and fossil sampling process, and produce trees of relationships that fit better with the fossil record. I develop extensions to these methods within the BEAST2 software framework, and these are available at my github. The methods I develop are always designed to solve particular empirical problems I encounter during my research.

Insect kidneys

The vast majority of animal species are insects. Many insects have a specialised excretory system, called the cryptonephridial system, which allows adaptation to exceedingly dry conditions. In 2014 we provided the first description of the embryonic development of the beetle excretory system, including the cryptonephridial system. I am interested in the cryptonephridial system as a model system for the study of convergent evolution.