Dear colleagues We are pleased to announce a new article: Cheng-Hsiu Tsai and R. Ewan Fordyce 2015 Ancestor-descendant relationships in evolution: origin of the extant pygmy right whale, Caperea marginata. Biology Letters doi: 10.1098/rsbl.2014.0875 http://rsbl.royalsocietypublishing.org/content/11/1/20140875 Abstract Ancestor–descendant relationships (ADRs), involving descent with modification, are the fundamental concept in evolution, but are usually difficult to recognize. We examined the cladistic relationship between the only reported fossil pygmy right whale, †Miocaperea pulchra, and its sole living relative, the enigmatic pygmy right whale Caperea marginata, the latter represented by both adult and juvenile specimens. †Miocaperea is phylogenetically bracketed between juvenile and adult Caperea marginata in morphologically based analyses, thus suggesting a possible ADR—the first so far identified within baleen whales (Cetacea: Mysticeti). The †Miocaperea–Caperea lineage may show long-term morphological stasis and, in turn, punctuated equilibrium. Available at http://rsbl.royalsocietypublishing.org/content/11/1/20140875 or email Tsai: cheng-hsiu.tsai@otago.ac.nz<mailto:cheng-hsiu.tsai@otago.ac.nz>; craniata@gmail.com<mailto:craniata@gmail.com> Regards and all the best, Tsai Cheng-Hsiu Tsai （蔡政修) PhD student, Department of Geology, University of Otago 360 Leith Walk (Courier) or PO Box 56 (Postal) Dunedin 9054, New Zealand Email: cheng-hsiu.tsai@otago.ac.nz<mailto:cheng-hsiu.tsai@otago.ac.nz>; craniata@gmail.com<mailto:craniata@gmail.com>