The San Diego Zoo Institute for Conservation Research (SDZICR) in San Diego, California, is a research organization that works to generate, use, and share information for the conservation of wildlife and their habitats. In 1975, Kurt Benirschke, a researcher at the University of California, San Diego (UCSD) who studied human and animal reproduction, and Charles Bieler, the director of the San Diego Zoo, collaborated to form the Center for Reproduction of Endangered Species (CRES). In 2009, the San Diego Zoo announced the creation of SDZICR, which expanded and replaced CRES, to provide central organization and management of scientific programs at the San Diego Zoo. By 2004, Allison Alberts was the director of research and for more than a decade oversaw the SDZICR's many research initiatives, including the collection and storage of genetic and reproductive information of rare and endangered animal and plant species.

Boris Ephrussi and George Wells Beadle developed a transplantation technique on flies, Drosophila melanogaster, which they described in their 1936 article A Technique of Transplantation for Drosophila. The technique of injecting a tissue from one fly larva into another fly larva, using a micropipette, to grow that tissue in the second larvae, was a means for investigating development of Drosophila. Through this technique, Beadle and Ephrussi studied the role of genes in embryological processes. Beadle and Ephrussi were the first to apply the transplantation method, which had previously been used in the study of larger insects, to the smaller sized Drosophila. Beadle and Ephrussi used this method of transplantation to determine if parts of the optic disc, the section of a larvae that later become the eye buds in the adult, could be extracted from one larva and transplanted into another. They later built upon this research to relate the production of molecules in cells to gene function.

In the article “The History of Twins, As a Criterion of the Relative Powers of Nature and Nurture,” Francis Galton describes his study of twins. Published in 1875 in Fraser’s Magazine in London, England, the article lays out Galton’s use of twins to examine and distinguish between the characteristics people have at birth and the characteristics they receive from the circumstances of life and experience. Galton calls those factors nature and nurture. Based on his study, Galton concluded that nature has a larger effect than nurture on development. By studying twins, Galton introduced a way to examine the effects of nature and nurture in people who were born with similar traits, which allowed him to focus on the effects of experience on a person’s development.

In 1990, Thomas J. Bouchard and his colleagues published the paper “Sources of Human Psychological Differences: The Minnesota Study of Twins Reared Apart” in Science Magazine. The paper described the results of a study initiated in 1979 on the development of twins raised in different environments. The scientists conducted their experiment at the University of Minnesota, in Minneapolis, Minnesota. The researchers physiologically and psychologically assessed monozygotic twins or triplets who were reared apart, comparing the similarity of those twins to twins who were reared together. The research team found that identical twins who are reared apart had the same chance of being similar as twins who were raised together. Bouchard and his colleagues concluded that genetic factors have a large influence on behavioral habits demonstrating the influence of the genetics on development.

National Geographic's documentary In the Womb: Identical Twins focuses on the prenatal development of human identical twins. Director Lorne Townend uses three-dimensional (3D) and four-dimensional (4D) ultrasound imaging and microscopy to depict twin development , genetic and epigenetic variations in the fetuses, and methods of fetal survival in the confines of the womb. Artist renditions of scientific data fill in areas of development inaccessible to the imaging tools. The 50-minute film describes the lives twins live after birth and describes new research that identical twins might not be as identical as once thought. In the womb: Identical Twins is a sequel to the 2005 National Geographic film In the Womb.

Lap-Chee Tsui is a geneticist who discovered the cystic fibrosis (CF) gene, and his research team sequenced human chromosome 7. As the location of the cystic fibrosis gene is now known, it is possible for doctors and specialists to identify in human fetuses the mutation that causes the fatal disease. Tsui's research also outlined the mechanisms for the development of cystic fibrosis, which were previously unknown.

Sir Francis Galton was a British science writer and amateur researcher of the late nineteenth century. He contributed greatly to the fields of statistics, experimental psychology and biometry. In the history of biology, Galton is widely regarded as the originator of the early twentieth century eugenics movement. Galton published influential writings on nature versus nurture in human personality traits, developed a family study method to identify possible inherited traits, and devised laws of genetic inheritance prior to the rediscovery of Gregor Mendel's work. His most important contribution to the field of embryology was his work in statistical models of heredity.

Cystic fibrosis (CF) is a fatal, inherited disease found in humans and characterized by buildup of thick, sticky mucus, particularly in the respiratory and digestive tracts. The abnormally thick mucus prevents the pancreas from functioning normally; it often leads to digestive problems and chronic lung infections. Cystic fibrosis is most prevalent in Caucasian individuals, and approximately 1 in every 29 individuals in the US is a carrier for the mutated CF gene. There are an estimated 30,000 reported cystic fibrosis cases in the US, and 70,000 reported cases worldwide, although the international number is undoubtedly low due to underreporting or early deaths.

In 2002 Eric Davidson and his research team published 'A Genomic Regulatory Network for Development' in Science. The authors present the first experimental verification and systemic description of a gene regulatory network. This publication represents the culmination of greater than thirty years of work on gene regulation that began in 1969 with 'A Gene Regulatory Network for Development: A Theory' by Roy Britten and Davidson. The modeling of a large number of interactions in a gene network had not been achieved before. Furthermore, this model revealed behaviors of the gene networks that could only be observed at the levels of biological organization above that of the gene.

Homeobox genes are a cluster of regulatory genes that are spatially and temporally expressed during early embryological development. They are interesting from both a developmental and evolutionary perspective since their sequences are highly conserved and shared across an enormously wide array of living taxa.