Although the split of coelacanths from other sarcopterygians is ancient, around 420 million years ago, the taxic diversity and the morphological disparity of the clade have remained relatively low, with a few exceptions. This supposedly slow evolutionary pace has earned the extant coelacanth Latimeria the nickname "living fossil". This status generated much interest in both extinct and extant coelacanths leading to the production of numerous anatomical studies.
View Article and Find Full Text PDFAmong New World direct-developing frogs belonging to the clade Brachycephaloidea (= Terraranae), there are several genera with uncertain phylogenetic placements. One notable example is the genus Niceforonia Goin Cochran 1963, which includes three species that are endemic to Colombia. Three specimens of the species Niceforonia nana were collected and for the first time the genus is included in a molecular phylogenetic analysis of mitochondrial (mtDNA; 12S and 16S) and nuclear (nucDNA; TYR and RAG1) markers.
View Article and Find Full Text PDFRegenerative medicine is a diverse and rapidly evolving field, employing core expertise from biologists, engineers, and clinicians. Recently the field has made significant progress towards regenerating or replacing tissues lost to age, disease or injury. Current strategies include transplantation of adult or pluripotent stem cells to replace tissue or support tissue healing.
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