This archive contains scripts, intermediate files and supplementary data tables for the PhD Thesis: The Genetic and Cellular Basis of Viviparity. All data, scripts and files were produced by John Laurence Smout unless otherwise specified. The archive consists of: chapter_2_full_tables.xlsx: Excel spreadsheet with complete supplementary tables for Chapter 2 of the thesis chapter_4_full_tables.xlsx: Excel spreadsheet with complete supplementary tables for Chapter 4 of the thesis data_archive: Folder containing scripts and intermediate files for analyses presented in Chapters 2, 3 and 4 of the thesis. Each chapter has its own subfolder and readme file with additional information.