"Morphology, Homology, Phylogeny, and Biogeography of Early Vertebrates and Fossil Fishes"

在特殊的化石沉积物中发现的化石鱼的完整骨骼提供了丰富的信息。在我的实验室里，我们专注于这些沉积物，以了解志留纪和泥盆纪早期（4亿至4.3亿年前）物种的起源，关系，生活方式和解剖特征，当时早期有颌骨的脊椎动物及其无颌亲属丰富多样。这些特殊的化石沉积在麦肯齐山脉，西北地区和加拿大北方的其他地方。 其中一个地点至少有73种早期脊椎动物，包括无颚类和与鲨鱼和硬骨鱼有关的早期有颚脊椎动物。大部分都是完整的骨架。其中一些可以让我们检查骨骼的生长。其他人告诉我们身体特征的进化，如成对的鳍，牙齿，耳朵和内脏。这些研究涉及与世界其他地方发现的化石进行仔细比较，并使用现代计算机方法重建生命树。 在摩洛哥的白垩纪，我们正在研究另一个非凡化石地点的海洋鱼类。许多种类的鱼类已被发现，并正在研究中，重点是它们的进化关系和地理历史。我们还研究了从化石鳞片和椎骨计算的化石鱼类的生长速率，以了解它们的生长速率如何响应古代气候变化。 现代鱼类的解剖学和DNA研究正在澄清它们之间的关系。新的关系思想引导我们重新审视同一群的化石，看看它们在过去是否得到了正确的解释。这种类型的研究将与美国的同事一起进行，重点是鳕鱼、海鲂、胡子鱼、鳟鱼、海盗鲈、梭子鱼和泥鱼科的淡水鱼。

Complete skeletons of fossil fishes found in exceptional fossil deposits yield a wealth of information. In my lab we focus on these deposits to learn about the origins, relationships, mode of life, and anatomical features of species that lived during Silurian and Early Devonian time (400 to 430 million years ago), when early vertebrates with jaws and their jawless relatives were abundant and diverse. These exceptional fossil deposits are in the Mackenzie Mountains, NWT and elswhere in northern Canada. One locality contains at least 73 species of early vertebrates, including jawless forms and early jawed vertebrates related to sharks and bony fishes. Most are complete skeletons. Some of them allow us to examine growth of the skeleton. Others tell us about the evolution of body features such as paired fins, teeth, ears, and guts. These studies involve careful comparisons with fossils found elsewhere in the world and use modern computerized methods of reconstructing the tree of life. In the Cretaceous of Morocco we are studying marine fishes from another extraordinary fossil site. Many species of fishes have been recovered and are under study, with emphasis on their evolutionary relationships and their geographic histories. We also study growth rates of fossil fishes calculated from fossil scales and vertebrae, to see how their growth rates responded to ancient climate change. The relationships of living fishes are being clarified by modern studies of their anatomy and their DNA. The new ideas of relationships lead us to re-examine fossils of the same groups, to see whether they have been interpreted correctly in the past. This type of study will be carried out with colleagues in the USA and will focus on the freshwater fishes in the cod, dory, beardfish, troutperch, pirateperch, pike, and mudminnow families.