Practical assessments of range production and utilization are based on forage weight estimates. In preparing these estimates moisture content in green vegetation offers some problems. The moisture component is not likely to be constant for a given species. Diurnal, seasonal and site variability have been well illustrated for agronomic and tree species (Salisbury, 1848; Jenkins, 1879; Miller, 1917; Pearson, 1924; Watkins, 1940; Parker, 1951; Ackley, 1954; Werner, 1954; Zohary and Orshan, 1956; Slatyer, 1959; Kozlowaki, 1965 and Jame son, 1966). Since variability is also likely for range plants, computations made on green weights are apt to be fallacious. It is a common practice, therefore, to express production on "water free" or "dry weight" basis. But the estimates of dry weight are made difficult by variations in herbage moisture. A variety of factors, relevant both to the vegetation and the site it occupies, would seem to account for variable moisture content. The prevalent methods for estimating moisture, however, seem to be more of a legacy from the past than an appreciation of ecological influences. Earlier investigators of pastures and fodder crops were largely agronomists interested in comparing yields. They were concerned primarily with irrigated crops where soil moisture is not a limiting factor and the ecological influences, such as humidity, rain, cloudy weather, dew, shade, exposure etc. are far from dominant (Atwater, 1869; Collier, 1881; Richardson , 1884; Ladd, 1888; Richardson, 1889; Morse, 1891 and Widstoe, 1897). The variations in water content and other components were accordingly related to stage of growth. Taking a cue from these studies agencies such as the United States Forest Service and Soil Conservation Service came to use certain reducing factors to convert green weight of range forage into dry weight. In developing these factors the type of vegetation and growth phases have been considered but ecological features and context have been neglected. The methodology adopted from pasture conditions became the accepted basis for making range management decisions (Range Memo, SCS-8, Soil Conservation Service, 1963; Range Analysis, Region IV, Forest Service, 1964). The influence of features of environment, particularly aspect, on growth differential, has long been recognized by foresters (Schlich, 1905; Champion, 1928 and Tourney, 1928). Plant physiologists have been aware of the significance of time-of-day on plant water for some time (Shreve, 1914; Miller, 1917). It is very probable that these influences express themselves in moisture content of herbage also. The investigations reported herein were conducted to define and assess the scope and intensity of some of these ecological features in modification of the moisture component of herbage. The objective is to determine whether differences in ecological context influence range herbage moisture to a sufficient extent to warrant consideration in developing conversion factors for deriving dry weights from green weights of vegetation samples. The appraisal should reaffirm present assumptions applied or yield more accurate adjustments for estimating forage production. In either circumstance the results should enhance the scientific basis of range management decisions.

Darbo tikslas: išmatuoti Lietuvoje paplitusių pilkųjų ir baltųjų kiškių kaukoles ir nustatyti šių kiškių kaukolių morfologinius tarprūšinius skirtumus. Tyrimas buvo atliekamas Kauno Tado Ivanausko zoologijos muziejuje, naudojant šiame muziejuje esančią kiškių kaukolių kolekciją. Osteometrinei analizei naudota 29 L. europaeus, 21 L. timidus kaukolės. Makroskopinei palyginamajai analizei naudota 68 L. europaeus, 24 L. timidus kaukolės. Osteometrinei analizei atlikti buvo pasirinkti 31 matavimas. 21 matavimas atliktas remiantis F. Palacios metodika, modifikuota F. Riga ir kt. (2001 m.), 10 matavimų atlikti pagal A. von den Driesch (1976) metodiką. Matavimai atlikti elektroniniu slankmačiu 0,01 mm tikslumu. Makroskopinė palyginamoji analizė buvo atliekama remiantis F. Palacios 1998 m. metodika. Tyrimo metu tarp rūšių nustatyta 15 statistiškai patikimų matmenų (P<0,05) ir 8 makrsokopinės anatomijos tarprūšiniai skirtumai. Išvados: pilkųjų kiškių veidinė dalis yra ilgesnė ir platesnė už baltųjų kiškių. Pilkųjų kiškių kiaušo dalis yra aukštesnė už baltųjų kiškių, tačiau baltiesiems kiškiams būdinga platesnė priekinė kiaušo dalis. Bendras kaukolės ilgis tarp rūšių nesiskiria, tačiau baltųjų kiškių kaukolės yra platesnės. Atlikus tarprūšinę pilkųjų ir baltųjų kiškių kaukolių ir apatinių žandikaulių osteologinę analizę, nustatyti 7 kaukolės ir 1 apatinio žandikaulio skirtumas. / Aim: To measure the spread of European and Mountain rabbit skulls in Lithuania as well as determine the morphological differences and variations of the skulls between the species. The study was conducted at Tadas Ivanauskas Zoology Museum in Kaunas, using the collection of the rabbit skulls presented there. In terms of the study, the 29 L. europaeus, 21 L. timidus skulls were used for Osteometric analysis while 68 L. europaeus, 24 L. timidus skulls were used for macroscopic comparative analysis. During the Osteometric investigation, thirty one measurement was performed in total, in which twenty one of them was based on F. Palacios methodology (modified F.Riga et al., (2001)) while other ten were based on A. von den Driesch (1976) methodology. Measurements were performed using electronic caliper with 0.01mm accuracy. Macroscopic comparative analysis was performed with reference to F. Palacios, (1998) methodology. As a result, fifteen statistically relevant dimensions (P<0,05) were discovered along with eight macroscopic anatomical variations between the species. Conclusions: The facial part of the European rabbit skull is longer and wider when compared to the Mountain rabbit skull. In addition, the neurocranium of the European rabbit skull is higher. However, Mountain rabbits typically have wider frontal area of the neurocranium. Overall length of the skull remains the same between the species, nevertheless, white rabbits were discovered to have generally wider skulls. The... [to full text]

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<p>The variety of fish species found at the archaeological sites indicates the exploitation of local and regional ecosystems. The focus of the fisheries varies from site to site. </p><p> The study is based on the analyses of faunal materials from 10 archaeological sites from Eastern Middle Sweden, Gotland, and Åland dating to approximately 3800 – 1850 B.C. The mainland assemblages are mainly burnt and highly fragmented. When comparing burnt and unburnt bone materials, results showed a marked predominance of fish specimens within the unburnt assemblages. The burnt bone materials showed a striking preponderance of marine mammals. The burning process impairs identification and quantification of fishbone. Species presence per context complemented summary data and showed that low and medium frequency species were handled more often than summary data indicate. Intra-site studies of burnt bones demonstrated the importance of detailed studies of the taphonomic history of the faunal assemblages.</p><p> At Ajvide on the island of Gotland, large amounts of well preserved unburnt faunal remains, and ca. 600 bone fishhooks have been unearthed. Replicas of fishhooks from this assemblage were subjected to strength test, osteometric, morphological, and breakage studies. Results point to an elaborated fishing technology for capturing medium sized cod. Incremental studies of cod otoliths (ear stones) from Ajvide showed that most cod were captured in fall and winter. A comparison with the contemporaneous Jettböle site on the Åland islands, showed that in general smaller cod and herring were captured there. </p><p> The ecological conditions were somewhat different during the Neolithic. The growth pattern for cod indicate a more rapid growth for young cod but with a lower asymptotic length compared to modern cod.</p>

The variety of fish species found at the archaeological sites indicates the exploitation of local and regional ecosystems. The focus of the fisheries varies from site to site. The study is based on the analyses of faunal materials from 10 archaeological sites from Eastern Middle Sweden, Gotland, and Åland dating to approximately 3800 – 1850 B.C. The mainland assemblages are mainly burnt and highly fragmented. When comparing burnt and unburnt bone materials, results showed a marked predominance of fish specimens within the unburnt assemblages. The burnt bone materials showed a striking preponderance of marine mammals. The burning process impairs identification and quantification of fishbone. Species presence per context complemented summary data and showed that low and medium frequency species were handled more often than summary data indicate. Intra-site studies of burnt bones demonstrated the importance of detailed studies of the taphonomic history of the faunal assemblages. At Ajvide on the island of Gotland, large amounts of well preserved unburnt faunal remains, and ca. 600 bone fishhooks have been unearthed. Replicas of fishhooks from this assemblage were subjected to strength test, osteometric, morphological, and breakage studies. Results point to an elaborated fishing technology for capturing medium sized cod. Incremental studies of cod otoliths (ear stones) from Ajvide showed that most cod were captured in fall and winter. A comparison with the contemporaneous Jettböle site on the Åland islands, showed that in general smaller cod and herring were captured there. The ecological conditions were somewhat different during the Neolithic. The growth pattern for cod indicate a more rapid growth for young cod but with a lower asymptotic length compared to modern cod.

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) are omnipresent and persistent environmental pollutants. In particular, 29 congeners are of special concern, and these are usually referred to as dioxin-like compounds (DLCs). In the European Union, the risks associated with DLCs in food products are estimated by a weighted sum of the DLCs’ concentrations. These weights, also called toxic equivalency factors (TEFs), compare the DLCs’ potencies to the most toxic congener, 2,3,7,8-tetrachloro-dibenzo-p-dioxin (2378- TCDD). The toxicological effects of PCDD/Fs and PCBs are diverse, ranging from chloracne and immunological effects in humans to severe weight loss, thymic atrophy, hepatotoxicity, immunotoxicity, endocrine disruption, and carcinogenesis in rodents. Here, the molecular structures of DLCs were used as the basis to study the congeneric differences in in vitro data from both human and rodent cell responses related to the aryl hydrocarbon receptor (AhR). Based on molecular orbital densities and partial charges, we developed new ways to describe DLCs, which proved to be useful in quantitative structure-activity relationship modeling. This thesis also provides a new approach, the calculation of the consensus toxicity factor (CTF), to condense information from a battery of screening tests. The current TEFs used to estimate the risk of DLCs in food are primarily based on in vivo information from rat and mouse experiments. Our CTFs, based on human cell responses, show clear differences compared to the current TEFs. For instance, the CTF of 23478-PeCDF is as high as the CTF for 2378-TCDD, and the CTF of PCB 126 is 30 times lower than the corresponding TEF. Both of these DLCs are common congeners in fish in the Baltic Sea. Due to the severe effects of DLCs and their impact on environmental and human health, it is crucial to determine if other compounds have similar effects. To find such compounds, we developed a virtual screening protocol and applied it to a set of 6,445 industrial chemicals. This protocol included a presumed 3D representation of AhR and the structural and chemical properties of known AhR ligands. This screening resulted in a priority list of 28 chemicals that we identified as potential AhR ligands.

The aim of the present work was to investigate the impact of the varying environmental conditions on the taxonomic and phenotypic diversification of a geographically widespread and ecologically successful Old World primate genus, the macaques (Cercopithecidae: Macaca). To this end, the relationship between geography, ecology, phylogeny, and phenotypic variation among macaques was investigated. Constraints to phenotypic variation – and thus evolution – were also analysed in the form of observed amounts of phenotypic variation and patterns of phenotypic integration. A total of 72 standard linear measurements of teeth and associated cranial and mandibular structures were taken for a total sample of 744 specimens from 13 species of macaques. Climate and ecological data were collated from the literature. Univariate and multivariate statistics were employed for the analysis. Patterns of variation, covariation, and allometry were analysed in the dentition, both within and between species. The ecogeographical analysis was carried out by means of two-block partial least squares and a type of multivariate regression, both in a phylogenetic framework. Phylogenetic signal was tested for by means of Blomberg’s K. Macaque teeth differ in their variability. All teeth covary with each other, although correlations are strongest within tooth classes. Size was a strong contributing factor to dental integration, as evinced by lower correlations between teeth once allometric effects were removed. Integration patterns also showed modularity between the anterior and the posterior dentition. Between-species variation in overall craniodental size was associated with temperature, latitude, and body size. Species also varied, albeit to a lesser degree, along an antero-posterior contrast in relative tooth size. Larger anterior were found to be associated with frugivory and tropical ecology, whereas a larger posterior dentition was linked to a more folivorous diet and temperate environments. The latter pattern was largely a function of phylogenetic relatedness. Phylogenetic signal was generally strong in the dentition, although it was substantially greater in the anterior teeth (incisors and canines) than in the posterior teeth (premolars and molars). Macaques show adaptive differentiation in body size in response to temperature along a latitudinal cline, corroborating the presence of the Bergmann effect in macaques. There was no conclusive support for further adaptive differentiation, despite an association between relative tooth size and diet. Allometry appears to channel evolutionary divergence of macaques along a line of least evolutionary resistance, and developmental modularity allows for partly uncoupled evolution of the anterior and posterior dentition. Future research should be aimed at broadening the taxonomic scope to include craniodental variation of the African papionins and cercopithecins in order to put the observed macaque patterns in a broader evolutionary context.