Release and distress calls in European spadefoot toads, genus Pelobates

The acoustic repertoire of most anurans, even common species, is still insufficiently known. Here, we present a thorough quantitative description of acoustic parameters in release and distress calls in the three European spadefoot toad species, genus Pelobates. We also explored the intra- and interspecific variation and effects of body size on acoustic traits. We analysed a total of 749 release calls of 34 individuals of Pelobates fuscus and P. syriacus, and 312 distress calls of 36 individuals of P. fuscus, P. syriacus and P. cultripes. Release calls consisted of a note with one to three initial pulses of lower energy and a group of consecutive pulses characterized by higher energy in both species analysed. The structure of the distress calls was similar in all three species: loud, explosive, cat meow-like, single multi-pulsed notes rich in harmonics. Some of the variation among species in acoustic parameters in the release and distress calls is related to body size. Acoustic properties for both release and distress calls showed high levels of variability in all species. This pattern of variation is different from what is regularly found in the more conservative advertisement calls, and we advocate that such high variability is possible because release and distress call are not signals with divergent evolutionary history among related species.This work received support from the SYNTHESYS Project http://www.synthesys.info/ which is financed by European Community Research Infrastructure Action under the FP7 ‘Capacities’ Programme, at the Museo Nacional de Ciencias Naturales (CSIC) [grant numbers SYNTHESYS ES-TAF-2814, SYNTHESYS ES-TAF-6704]; the Romanian National Authority for Scientific Research, CNCS –UEFISCDI [grant number PN-II-ID-PCE-2011-3-0173] and CCCDI-UEFISCDI – project No. 105 BM/2017; Sao Paulo Research Foundation (FAPESP) by a doctoral grant [grant number #2009/13987-2] and a fellowship [grant number #2013/21519-4]; The National Council for Scientific and Technological Development (CNPq) provided a fellowship [grant number #150041/2017-9]. Partial funding for acoustical analyses was provided by Ministerio de Ciencia e Innovación, Spain, projects TATANKA CGL2011-25062, CGL2010-09700; Ministerio de Economía y Competitividad, Spain project CGL2011-16159-E.Peer reviewe

Microevolution and maternal effects on tadpole Rana temporaria growth and development rate

Can variation in egg size explain the local variation in tadpole growth and development of the common frog Rana temporaria or are other mechanisms, e.g. microevolution, involved? To study this, tadpoles were raised in outdoor tanks. Each tank housed tadpoles from one clutch. Eggs were collected during 2 years from six different ponds and their sizes were measured. Large eggs gave rise to tadpoles that grew and developed faster than those hatched from small eggs. Tadpoles from large eggs thus metamorphosed earlier but, because they grew for a shorter time, size at metamorphosis was not affected by initial egg size. Tadpoles from different ponds differed in strategy; after correcting for egg size effects, tadpoles from some ponds tended to metamorphose earlier and at a larger size than those from others. These ponds occasionally dry out during or before the tadpoles period of metamorphosis. I argue that the detected pond differences are genetically based and represent a case of microevolution