Differential effects of pH and temperature on embryonic development in the British newts (Triturus)

Changes in the water quality and temperature relationships of ponds may affect the structure of amphibian assemblages. The survival, time to hatching, hatching size and hatching stage of newt embryos were studied in the three British species ( Triturus cristatus, T. helveticus and T. vulgaris ), at two temperatures and two pHs. All T. cristatus embryos failed to hatch at pH 4.5, whereas over 80% of T. helveticus and T. vulgaris embryos hatched successfully at the same pH. At pH 7.5, T. cristatus survival was the same as the other two species, after the 50% mortality due to the homomorphism of chromosome 1 was taken into account. Temperature had no effect on survival of embryos. Time to hatching was two to four times longer at 12°C than at 17°C. Low pH shortened development time in T. vulgaris but not in T. helveticus . Low pH, but not temperature, affected size at hatching, with T. helveticus and T. vulgaris embryos emerging at a smaller size and earlier stage of development under acidic conditions. This reduction of size at low pH affected T. vulgaris more than T. helveticus . We predict that T. cristatus embryos will be the most vulnerable of the three species to acidification in nature. Warm ponds will result in rapid embryonic development, but T. helveticus and T. vulgaris larvae hatching in acid ponds will do so at a smaller size and earlier stage of development. The pattern of vulnerability to acidification within amphibian assemblages may change during ontogeny.     

The 18S ribosomal RNA sequence of the sea anemone Anemonia sulcata and its evolutionary position among other eukaryotes

Evolutionary trees based on partial small ribosomal subunit RNA sequences of 22 metazoa species have been published [(1988) Science 239, 748-753]. In these trees, cnidarians (Radiata) seemed to have evolved independently from the Bilateria, which is in contradiction with the general evolutionary view. In order to further investigate this problem, the complete srRNA sequence of the sea anemone Anemonia sulcata was determined and evolutionary trees were constructed using a matrix optimization method. In the tree thus obtained the sea anemone and Bilateria together form a monophyletic cluster, with the sea anemone forming the first line of the metazoan group.     

Reassessment of the vocal repertoire of a nest-building gladiator frog,Boana pardalis (Anura,Hylidae, Cophomantinae): implications for its diagnosis within the B. faber species group

In this study, we re-describe the advertisement and territorial calls of Boana pardalis, carry out an acoustic comparison between the studied species and the other congeners of the B. faber group, and report for the first time the tympanic amplexus for the studied species. The advertisement call of B. pardalis can be used to supplement its diagnosis in the B. faber group based on temporal call traits, e.g. emission rate and emission pattern, as well as the call envelope.     

Movement patterns and space use of the first giant anteater (Myrmecophaga tridactyla) monitored in São Paulo State,Brazil

This study analyzes a giant anteater’s (Myrmecophaga tridactyla) movement patterns and space use in São Paulo, Brazil. It is the first study to track a giant anteater with Iridium-GPS. The anteater traveled an average distance of 1326 m day^–1 with an average speed of 1.04 m min^–1. Home range by Kernel was 2.46 km² while the core area was 0.75 km², and estimates by Brownian bridge and minimum convex polygon were also provided. The anteater used shrub savanna, open savanna, and water habitats more than expected. Monitoring ended just after 10 days when the female giant anteater’s GPS was found on an illegal trail.     

Structure and growth pattern of the bizarre hemispheric prominence on the rostrum of the fossil beaked whale Globicetus hiberus (Mammalia,Cetacea, Ziphiidae)

The rostrum of most ziphiids (beaked whales) displays bizarre swollen regions, accompanied with extreme hypermineralisation and an alteration of the collagenous mesh of the bone. The functional significance of this specialization remains obscure. With the voluminous and dense hemispheric excrescence protruding from the premaxillae, the recently described fossil ziphiid Globicetus hiberus is the most spectacular case. This study describes the histological structure and interprets the growth pattern of this unique feature. Histologically, the prominence in Globicetus is made up of an atypical fibro‐lamellar complex displaying an irregular laminar organization and extreme compactness (osteosclerosis). Its development is suggested to have resulted from a protraction of periosteal accretion over the premaxillae, long after the end of somatic growth. Complex shifts in the geometry of this tissue are likely to have occurred during its accretion and no indication of Haversian remodeling could be found. X‐ray diffraction and Raman spectroscopy indicate that the bone matrix in the premaxillary prominence of Globicetus closely resembles that of the rostrum of the extant beaked whale Mesoplodon densirostris: apatite crystals are of common size and strongly oriented, but the collagenous meshwork within bone matrix seems to be extremely sparse. These morphological and structural data are discussed in the light of functional interpretations proposed for the highly unusual and diverse ziphiid rostrum. J. Morphol. 277:1292–1308, 2016. © 2016 Wiley Periodicals, Inc.     

Behavioral laterality in captive bonobos (Pan paniscus): Replication and extension

We report observational data on behavioral laterality in 10 captive bonobos (Pan paniscus)at the San Diego Zoo. The unimanual measures include carrying, leading limb in locomotion, self-touching, face-touching, reaching, and gestures. We also recorded bimanual feeding in these subjects. A significant population level left-hand bias exists for carrying. Right-hand biases occur for leading limb in locomotion and gestures. During bimanual feeding, the bonobos hold food items with the left hand while feeding with the right hand. Overall, bonobos exhibit behavioral asymmetries that are similar to previous findings in other pongid ape species. The asymmetries in gestures and bimanual feeding represent novel findings with theoretical implications for the origins of tool use and language.     

Metabolic conversion of the biologically active phospholipid, lysophosphatidic acid, in fibroblasts.

Lysophosphatidic acid (3-sn-lysophosphatidic acid; LPA) can activate cells similar to hormones and growth factors. We have considered the question whether metabolic conversion of LPA taken up by the cell could be of any importance in this activation. Addition of [14C-glycerol]LPA to quiescent Rat-1 fibroblasts resulted in rapid formation of [14C]monoacylglycerol (MG), closely followed by accumulation of [14C]triacylglycerol. Only very little [14C]diacylglycerol and [14C]phosphatidic acid was formed (approx. 100-fold less than MG). MG, when added exogenously to cells, lacks detectable biological activity. The results suggest that LPA itself, rather than one of its metabolites is the biologically active principle.