Mathi Thiruppathy

Abstract How novel structures emerge during evolution has long fascinated biologists. A dramatic example is how the diminutive bones of the mammalian middle ear arose from ancestral fish jawbones1. In contrast, the evolutionary origin of the outer ear, another mammalian innovation, remains a mystery, in part because it is supported by non-mineralized elastic cartilage rarely recovered in fossils. Whether the outer ear arose de novo or through reuse of ancestral developmental programs is unknown.

Abstract Cartilage is a dynamic tissue during development, repair, and disease. Within developing endochondral bones, chondrocytes at growth plate edges transition to osteoblasts, adipocytes, and other connective tissue in the marrow cavity, and in diseases such as Multiple Osteochondromas (MO) chondrocytes form abnormally around growth plates and contribute to ectopic bone.

Decision letter after peer review: Thank you for submitting your article "Gill developmental program in the teleost mandibular arch" for consideration by eLife. Your article has been reviewed by 2 peer reviewers, and the evaluation has been overseen by a Reviewing Editor and Marianne Bronner as the Senior Editor. The following individual involved in the review of your submission has agreed to reveal their identity: Craig T Miller (Reviewer #2).