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Over the past decade, we have seen a wonderful interconnectedness between the fields of developmental biology and evolutionary biology. Understanding how organisms achieve their uniqueness, be it morphological or mechanistic, is best understood with a developmental approach. However, by understanding the greater picture of where these organisms fit in evolutionary history provides a much richer understanding of diversity. Thus, while traditional developmental approaches focused on model organisms that became the hallmark of how development operates within entire clades, research questions are now more focused on a wider breath of organisms. In Part One of this Special Issue on Advances in Evolutionary and Developmental Biology, we learn about the many reasons why non-model organisms provide enormous insights into how developmental processes have changed over evolutionary time, how new genetic and genomic resources as well as advances in imaging have moved the field forward and where current challenges lie. From butterflies and annelids to skates and gars and on to owls and chameleons, this Special issue has it all! This Special Issue harnesses the uniqueness of non-model organisms and shows why we need to expand our view of development to beyond a handful of traditional model organisms. Diaz et al examine neural crest formation and migration in the veiled chameleon, the first examination in a squamate, a lineage that comprises 10,000 phylogenetically diverse taxa. The value of studying non-model organisms is further demonstrated by the comparative assessments of the developing skeleton in the spotted gar vs mouse and the barn owl vs chicken (eg, in Rostampour et al and Franz-Odendaal and Krings, respectively). A unique p63-driven GRN for tooth development and heterochrony within the vertebrate eye is revealed! Surprising results were obtained when Kostyuchenko et al explored the expression of FoxA, a gene known for its involvement in the gut GRN, in two closely related polycheate worms. Not only did they identify a previously unknown and possibly ancestral role for this gene, namely during gastrulation morphogenesis, they also discovered a key regulator of gut development. Their findings suggest that FoxA may be a late evolutionary acquisition of chordates. Another study, by Theodosiou and Oppong, demonstrates how the study of spiral intestine development in the little skate is a good model system to study the evolution of morphological asymmetries. A review article discussing the mechanisms of cardiac development across taxa (cephalopods, insects and beyond) reveals that understanding the evolutionary history of the cardiac system from a developmental perspective provides important insights into congenital cardiac malformations in humans. Similarly the critical commentary by Grinblat and Lipinski demonstrates the value of cross species comparisons in helping to solve mysteries of human congenital birth defects. Thus whether one examines a well-known gene in a non-model organism or the development of a structure not present in the traditional model organisms, new and important discoveries that provide valuable insight into phenotypic diversification are often revealed. These studies exemplify how evo-devo is a powerful approach to unveiling mechanisms underlying morphological diversity across evolutionary timescales. In order to ensure the field keeps abreast of mainstream developmental biology, evo-devo researchers are faced with the exciting challenge of taking new tools that have been developed and optimized for use in conventional model organisms and applying them to new species to generate new evo-devo toolkits and resources. This practice often has a domino effect, leading to the widespread use of the latest techniques in many new systems. For example, the Tol2 transgenesis system, which takes advantage of a transposable element identified in the Japanese medaka fish, was originally developed as a tool in zebrafish for introducing insertions into the germline genome and was gradually expanded for use in traditional model organisms, including mouse, frog and chicken. This ability to make stable transgenic lines is a key feature that can greatly expand the tractability of a new model system, allowing functional genetic studies. In this Special Issue, Stahl et al use the Tol2 transposase system to generate stable transgenic lines in the Mexican tetra, Astynax mexicanus, a cavefish model that is an excellent system for studying the evolution of morphological diversity, behavior and physiology. This advancement, which also uses vectors originally developed in zebrafish, will allow for the speedy generation of new A mexicanus transgenic lines, while also facilitating cross-species genetic comparisons. In addition to genetic tools, genomic resources are key for advancing studies in non-model systems. Here, Pinto et al present a new multi-tissue transcriptome for the veiled chameleon. This DOI: 10.1002/dvdy.71