Glossary

**Richard Owen** (20 July 1804 – 18 December 1892) was a British comparative anatomist and paleontologist who, in 1842, established the taxon **Dinosauria** to encompass three genera of fossil reptiles—Megalosaurus, Iguanodon, and Hylaeosaurus—that he recognized as sharing key anatomical features distinct from all known living reptiles. Owen identified their common characteristics as including multiple fused sacral vertebrae, immense body size exceeding that of any extant reptile, and columnar, upright limbs positioned beneath the body rather than sprawling laterally. Beyond naming the dinosaurs, Owen made foundational contributions to comparative anatomy, most notably formulating the modern definition of **homology** in 1843, describing it as "the same organ in different animals under every variety of form and function." He was instrumental in establishing the British Museum (Natural History)—now the Natural History Museum in London—which opened in 1881. Owen's legacy is complex: while his scientific contributions were substantial and enduring, his career was marked by accusations of appropriating colleagues' work, his vociferous opposition to Darwin's theory of natural selection, and his erroneous claims in the hippocampus debate with Thomas Henry Huxley.