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1.
Antonieta Labra & Hermann M. Niemeyer 《Ethology : formerly Zeitschrift fur Tierpsychologie》2004,110(8):649-662
The ability to assess and respond to predation risk is a strong selective force. Detection of predators is carried out by one or more sensory modalities, but the use of chemoreception has significant advantages. This study examines the chemosensorial assessment of snake predation risk and corresponding behaviours in different species and populations of Liolaemus lizards naturally exposed to different levels of snake predation pressure. The species studied were sympatric (Liolaemus lemniscatus), parapatric (L. nigroviridis) and allopatric (L. fitzgeraldi) to the saurophagous snake, Philodryas chamissonis. Additionally, two populations of L. lemniscatus from areas differing in snake densities were compared. Chemo‐assessment of predation risk was determined by comparing the number of tongue‐flicks (TF) and the behavioural responses of lizards submitted to three treatments (with semiochemicals of snake, conspecifics, and without semiochemicals – control). The results suggest that Liolaemus lizards can chemo‐assess snake predation risk, but this was modulated by the predation pressure experienced by lizards in their natural habitats. When exposed to snake semiochemicals, the sympatric prey showed less chemical exploratory behaviour (i.e. lower number of TF), a higher frequency of antipredator behaviours that would reduce its detection by a predator, and did not show the behaviour triggered by conspecific semiochemicals. The parapatric prey showed similar number of TF across different treatments, suggesting an absence of recognition of snake semiochemicals; however, it did show antipredatory behaviours when confronted with snake semiochemicals. The allopatric prey showed similar behaviour in all treatments. Both populations of the sympatric species, L. lemniscatus, showed a similar ability to detect predation risk when confronted with snake semiochemicals (i.e. similar number of TF), but antipredatory behaviours were diminished, and marking behaviours were present in the population subject to lower predation pressure. Relaxed predation pressure from a predator that releases and detects semiochemicals had similar consequences at species and population levels. 相似文献
2.
Summary We document activity field temperatures, daily activity patterns, and extent of thermoregulation in four species of Liolaemus lizards inhabiting at high altitude (above 3500 m) in the Andes of northern Chile. These four species have similar activity field temperature (Tb near 29°C) despite their being distributed at different altitudinal belts. However, conspicuous differences exist between higher-altitude (L. alticolor and L. jamesi) and lower-altitude (L. islugensis and L. ornatus) lizards regarding extent of thermoregulation and activity period. Some differences in morphology, behavior, and patterns of microhabitat occupancy are also apparent among these four species and are seemingly related to the thermal environment to which they are subjected. In comparison to eight low-altitude Liolaemus species in central Chile (Tb near 35°C) the four high-altitude species in northern Chile have lower activity field temperature. The latter is apparently due to the constraints imposed by the harsh Andean thermal environment, a hypothesis supported by the fact that high-altitude Liolaemus lizards under laboratory conditions demonstrate body temperatures that exceed by 5°C or more, those recorded in the field. 相似文献
3.
Dietary fibres from Ulva lactuca (L.) Thuret (sea lettuce) and Enteromorpha compressa (L.) Grev. (A.O. nori) were measured according to a ‘standard’ method and a ‘physiological’ protocol simulating the gastric
and intestinal environments. U. lactuca contained 15.8–8.0% soluble and 24.2–32.6% insoluble fibres according to the ‘standard’ and ‘physiological’ methods, respectively.
For E. compressa, these values were 14.9–15.9 and 21.6–28.7%, respectively. For both algae, the composition suggests that the soluble fibres
were xylorhamnoglycuronans sulphates and insoluble fibres were essentially composed of glucans. No marked chemical compositional
variation was observed between soluble fractions extracted under the simulated gastric and intestinal conditions. Fibres in
both algae are hydrophilic but the water holding capacities were higher after extraction of soluble fibres (5.5–9.5 g g−1 for the dry algae; 14.0–16.0 g g−1 for the standard insoluble fibres). Water soluble fibres demonstrated low intrinsic viscosities at 37 °C in buffers, particularly
those from E. compressa (36.0–36.5 ml g−1), and was affected by pH for those of U. lactuca (147.5 ml g−1 at pH 3.0 and 175.0 ml g−1 at pH 7.3). 相似文献
4.
Enrique Rodríguez-Serrano Carlos A. Navas Francisco Bozinovic 《Journal of thermal biology》2009,34(6):306-309
Two competing hypotheses have been suggested to explain thermal sensitivity of lizards to environmental conditions. These are the static and the labile hypotheses. The static hypothesis posits that thermal physiology is evolutionary conservative and consequently relatively insensitive to directional selection. Contrarily, the labile hypothesis states that thermal physiology does respond readily to directional selection in some lizard taxa. In this paper, we tested both hypotheses among species of Liolaemus lizards. The genus Liolaemus is diverse with about 200 species, being broadly distributed from central Perú to Tierra del Fuego at the southern end of South America. Data of field body temperature (Tb) from Liolaemus species were collected from the literature. Based on the distributional range of the species we also collected data of mean annual ambient temperatures. We observed that both the traditional analysis and the phylogenetic approach indicate that in the genus Liolaemus Tb of species varies in a manner that is consistent with ecological gradient of ambient temperature. The data suggest that the thermal physiology of Liolaemus lizards is evolutionarily flexible, and that this plasticity has been partially responsible for the colonization of a wide array of thermal environments. 相似文献
5.
Makoto Okamoto Keiichi Takeda Hiroya Sugisaki Takashi Asahida 《Ichthyological Research》2007,54(1):61-67
The early life stages of Lestidiops sphyraenopsis (Paralepididae) are described on the basis of 14 specimens [7.8 mm in notochord length (NL)–88.6 mm in standard length (SL)]
collected from the western North Pacific, and the holotype of Stemonosudis molesta is reexamined. Larval L. sphyraenopsis occurred in the Kuroshio waters, and juveniles were taken in the Kuroshio–Oyashio transition waters. Diagnostic characters
of larval and juvenile L. sphyraenopsis are 96–101 myomeres; 27–31 anal fin rays; 4–9 peritoneal pigment sections in larvae (7.8 mm NL–27.3 mm SL); dorsal and anal
pigment patches present; and anus located anterior to a vertical through dorsal fin origin. Stemonosudis molesta, known only from the holotype from the South Pacific, is similar to immature specimens of L. sphyraenopsis, but can be clearly distinguished from the latter by having higher vertebral counts (105 vs. 96–101) and by morphometric
and pigment differences. Consequently, S. molesta is a valid species, and the distribution of L. sphyraenopsis is restricted to the North Pacific. 相似文献
6.
Summary In recent years, public concern about indoor mould growth has increased dramatically in the United States. In this study,
lactic acid bacteria (LAB), which are known to produce antimicrobial compounds important in the biopreservation of food, were
evaluated to determine if the same antimicrobial properties can be used to inhibit mould fungi that typically colonize wood.
Based on biomass measurement, cell-free supernatants from Lactobacillus casei subsp. rhamnosus and Lactobacillus acidophilus grown in deMan Rogosa Sharpe (MRS) broth inhibited 95–100% growth of three mould fungi and one stain fungus associated with
wood-based building materials. Lactic acid and four unknown compounds ⩽ kDa molecular weight were fractionated from the culture
supernatant by thin layer chromatography and high-performance liquid chromatography. Antifungal activity, which was attributed
to one or more unknown metabolites, was retained during heating and neutralization. A 1:2 dilution of L. casei supernatant inhibited 100% growth of all test fungi. 相似文献
7.
The positive effects of the tube dwelling polychaete Lanice conchilega for the associated benthic community emphasizes this bio-engineer’s habitat structuring capacity (Rabaut et al. in Estuar
Coastal Shelf Sci, 2007). Therefore, L. conchilega aggregations are often referred to as reefs. The reef building capacity of ecosystem engineers is important for marine management
as the recognition as reef builder will increase the protected status the concerned species. To classify as reefs however,
bio-engineering activities need to significantly alter several habitat characteristics: elevation, sediment consolidation,
spatial extent, patchiness, reef builder density, biodiversity, community structure, longevity and stability [guidelines to
apply the EU reef-definition by Hendrick and Foster-Smith (J Mar Biol Assoc UK 86:665–677, 2006)]. This study investigates
the physical and temporal characteristics of high density aggregations of L. conchilega. Results show that the elevation and sediment consolidation of the biogenic mounds was significantly higher compared to the
surrounding unstructured sediment. Areas with L. conchilega aggregations tend to be extensive and patchiness is high (coverage 5–18%). The discussion of present study evaluates whether
L. conchilega aggregations can be considered as reefs (discussing physical, biological and temporal characteristics). Individual aggregations
were found to persist for several years if yearly renewal of existing aggregations through juvenile settlement occurred. This
renewal is enhanced by local hydrodynamic changes and availability of attaching structures (adult tubes). We conclude that
the application of the EU definition for reefs provides evidence that all physical and biological characteristics are present
to classify L. conchilega as a reef builder. For temporal characteristics, this study shows several mechanisms exist for reefs to persist for a longer
period of time. However, a direct evidence of long-lived individual reefs does not exist. As a range of aggregation development
exists, ‘reefiness’ is not equal for all aggregations and a scoring table to quantify L. conchilega reefiness is presented. 相似文献
8.
The chemical composition of rainwater is altered upon its passage through tree canopies. In order to investigate how rainwater
chemistry is affected by canopy-dependent processes in characteristic forest types of Northwest German sandy lowland regions
– oak–birch-forests, Betula pubescens Ehrh. swamp forests, and stands of Pinus sylvestris L. – comparative studies on the chemical composition of throughfall were carried out at seven forest sites, situated in close
proximity within a nature reserve. Additionally, rainwater was sampled at three heathland sites for analysis of open-field
precipitation and at three sites along an oak–birch-forest edge. Throughfall concentrations of most of the parameters analysed
were significantly higher than open-field concentrations, especially with regard to electric conductivity, NH4-N, K+, and KMnO4-index. Ion concentrations in throughfall were the lowest in a 10-year-old stand of Betula pendula Roth. and Pinus sylvestris and in a Betula pubescens swamp forest and were highest beneath a stand of Pinus sylvestris. Except for Na+, Cl−, and NO3−, ion concentrations in both throughfall and open-field precipitation increased during the growing season (May–October). In
throughfall, Ca2+, Mg2+, K+, and Mn2+ were strongly correlated. Enrichment ratios between throughfall and open-field deposition varied among sites and elements
and were the highest for K‰+, Mg2‰+, and Mn2‰+. Estimates of canopy leaching indicated high leaching rates of K‰+ and Mn2‰+ and moderate leaching of Mg2‰+. The contribution of foliar leaching to throughfall deposition was higher at the deciduous than at the coniferous stands. 相似文献
9.
The effect of chemical additives (acetosyringone, AS; L-cysteine, CYS; dithiothreitol, DTT; glutathione, GSH; cellulase, CEL;
pectinase, PEC) and light regimes (16/8 light/dark photoperiod, 16L/8D; continuous light, 24L; continuous dark, 24D) applied
during cocultivation procedure of pea explants with Agrobacterium tumefaciens on transformation efficiency was studied. A hypervirulent strain of A. tumefaciens EHA 105 with two plasmids, namely pGT89 and pBIN19, both carrying reporter gus-int gene, and bar or nptII selectable marker gene, respectively, was used for genetic transformation of cotyledonary node explants of three dry seed
pea cultivars Adept, Komet and Menhir. The focus was laid on cocultivation step (48 h) of transformation protocol. After chemical
or physical treatments, transient GUS expression was recorded 20 days after cocultivation as a measure of successful transformation,
using a four category scale (0 – without GUS expression, 1 – weak, 2 – medium and 3 – strong GUS expression) for calculation
of IGE (Intensity of GUS Expression). Of the tested chemical cocultivation additives, 100 μM AS and 50 mg CYS significantly
improved GUS expression (IGE value), while DTT, GSH and both macerating enzymes (CEL, PEC used either separately or in combination)
either had no positive effect or were even negative. There were no statistically significant differences between the light
regimes tested. Nevertheless, cocultivation in 24L, without chemical additives, reproducibly resulted in the highest frequency
of explants scored in category 3 of GUS expression (followed by 24D and 16L/8D treatment). However, application of 100 μM
AS reverted this trend. Cv. Adept yielded higher transformation frequencies than cvs. Menhir and Komet. Plasmid pGT89 produced
a higher IGE value than pBIN19. Based on our results, the improved cocultivation step for pea consists of 48 h cocultivation
at 20 ± 2°C, with 50 mg l−1 CYS and 100 μM AS, 16L/8D photoperiod (or without AS in continuous light). 相似文献
10.
Phylogeographic history of Patagonian lizards of the Liolaemus elongatus complex (Iguania: Liolaemini) based on mitochondrial and nuclear DNA sequences
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Cintia Débora Medina Luciano Javier Avila Jack Walter Sites Jr Mariana Morando 《Journal of Zoological Systematics and Evolutionary Research》2017,55(3):238-249
In this study, we present a phylogeographic analysis of a group of lizards distributed in north‐western Patagonia, the Liolaemus elongatus complex. We sequenced 581 individuals for one mitochondrial gene (cytochrome‐b), and for a subset, we sequenced another mitochondrial gene (12S rRNA) and two nuclear genes: kinesin family member 24 (KIF24) and the anonymous nuclear locus LDAB1D. We estimated gene trees, mitochondrial and nuclear haploytpe networks, standard molecular diversity indices, genetic distances between lineages and Bayesian skyline plots. Our results provide evidence for recognition of seven species previously described within the L. elongatus complex: Liolaemus antumalguen, Liolaemus chillanensis, Liolaemus carlosgarini, Liolaemus burmeisteri, Liolaemus smaug, Liolaemus elongatus and Liolaemus crandalli, but we did not find sufficient evidence to support Liolaemus choique, Liolaemus shitan or Liolaemus sp. 6 as distinct species. We identified four candidate species (Liolaemus sp. 1, Liolaemus sp. 2, Liolaemus sp. 3 and Liolaemus sp. 7), and we discuss evolutionary processes that may have contributed to the origin of these lineages and their taxonomic and conservation implications. 相似文献
11.
Atrazine Tolerance of Grass Species with Potential for Use in Vegetated Filters in Australia 总被引:2,自引:0,他引:2
The response of introduced (Pennisetum clandestinum Hochst.) and native (Stipa aristiglumis F. Muell., Themeda australis (R. Br.) Stapf, Danthonia spp. (L.) grasses to the herbicide atrazine was studied in plants with the potential for use in vegetated filters (biofilters)
designed to reduce chemical loads in agricultural runoff. The response was detected by photosynthetic inhibition using leaf
chlorophyll fluorescence. With continuous short-term (14 days) dosing with atrazine in sand culture, P. clandestinum showed the greatest tolerance, regardless of the dose (20–500 μg/L). In a clay vertosol soil in the glasshouse, the four
species were tolerant to longer-term (84 days) application of three successive doses of simulated run-on, each dose containing
100 μg/L atrazine, a concentration which is comparable to the highest reported in runoff from agricultural land in Australia.
Even with a subsequent single atrazine dose at ∼
∼5000 μg/L, established plants of the four species showed signs of quick recovery (7–21 days) to normal photosynthetic activity.
In a field experiment with simulated run-on, applied to P. clandestinum pasture in sandy loam soil, repeated doses at concentrations up to 1000 μg/L gave no significant response; only a subsequent
single dose of 5000 μg/L had significant effects, from which plants soon recovered. Although damage from atrazine can be demonstrated
with continuous dosing in non-adsorbing media, in soil culture the tolerance of the four selected species to repeat doses
of atrazine shows they may be used confidently for biofiltering purposes. P. clandestinum was especially tolerant. 相似文献
12.
Production, turnover and nutrient dynamics of floating leaves of Nymphaea alba L. and Nuphar lutea (L.) Sm. were studied in four aquatic systems in The Netherlands, differing strongly in water quality. Production was 108–447
g AFDW.m−2 for N. lutea and 319–348 g AFDW.m−2 for N. alba. Turnover ranged from 3.6 to 4.4 without much difference between the sites and the species. During senescence 60–70% of the
N and P from the leaves was resorbed by both of the plant species. The nutrient flow from the floating leaves into the detritus
food chain differed considerably between the species and sites studied, mainly because of the differences in production. The
data suggest that production is strongly influenced by the environment, whereas turnover and nutrient resorption during senescence
seem to be plant characteristics. There was little difference in dynamics of the chlorophyll-α concentration in the leaves
of the two species, irrespective of the growing site. Floating leaves of both species lost about 70% of their area due to
fragmentation in the alkaline waters, whereas in the acid water very little fragmentation was observed. 相似文献
13.
Anirban Chakraborty Martien J.P. van Oijen Kelvin K.P. Lim Yukio Iwatsuki 《Ichthyological Research》2006,53(1):41-46
A trichiurid, Lepturacanthus roelandti (Bleeker, 1860), previously regarded as a synonym of L. savala (Cuvier, 1829), is redescribed as a valid species on the basis of the holotype of the former and four non-type specimens.
This species differs from the two valid congeners, viz., L. savala and L. pantului (Gupta, 1966), in having a gold sheen or yellowish-silver color when fresh (vs. steel-blue with metallic sheen in the latter
two), posterior margin of maxilla reaching or extending beyond a vertical through hind eye margin (vs. not extending beyond
a vertical through hind eye margin), pectoral fin slightly longer than snout (vs. slightly shorter than snout), tip of pectoral
fin clearly extending beyond dorsal outline when vertically orientated (vs. not reaching dorsal outline), gill rakers absent
or reduced to stiff ossified structures (vs. well developed, spinelike), first anal fin spine situated below the 40th–43rd
dorsal fin ray (vs. below 35th–39th in L. pantului and 35th–40th in L. savala), precaudal vertebrae 42–43 (vs. 35–39 in L. pantului and 36–40 in L. savala), and attaining larger sizes [882–1200 mm in total length (TL) vs. less than 800 mm TL in the latter two]. 相似文献
14.
Pieter Pypers Liesbeth Van Loon Jan Diels Robert Abaidoo Erik Smolders Roel Merckx 《Plant and Soil》2006,283(1-2):251-264
There are several indications that legumes are capable of accessing sparingly soluble phosphorus (P) in the soil through root-induced
processes. We hypothesize that this plant-induced mobilization of P can be demonstrated if the plant accessible P assessed
by isotopic dilution (‘L-value’) exceeds the corresponding values assessed in soil extracts (‘E-values’). A greenhouse experiment was set up to assess if L/E ratios are affected by P supply and by crop type. The L- and E-values were determined in three P-deficient soils of the Nigerian Northern Guinea savanna (NGS), applied with various rates
of TSP, for two cowpea varieties (Vigna unguiculata L., cv Dan-Ila and cv IT-82D-716) and maize (Zea mays L., cv oba super I) as a reference. Plants grown in control soils were severely P-deficient. Plant growth and shoot P uptake
significantly increased with increasing P application in all three soils and for all crops, but relative yield and shoot-P
responses to P application were similar between maize and cowpea. Both L- and E-values increased with increasing P application. Average L/E ratios for maize were 1.4±0.3 and were unaffected by the P application.
For cowpea in contrast, L/E ratios were 3.1±0.2 (significantly larger than one) in one of the three control soils and significantly
decreased to 1.3±0.1 at largest P supply. Elevated L/E ratios in cowpea were not associated with an increase in P uptake compared
to the other two control soils in which no increase in L/E ratio was observed. It is concluded that cowpea is able to access
non-labile P under P-deficient conditions. However, this process cannot overcome P deficiency in these soils, probably because
P uptake is limited by the small P concentration in the soil solution (1–2 μg P L−1) and this limitation is not overcome by an increase in the accessible soil P quantity (L-value). 相似文献
15.
Larval mortality ofNeodiprion sertifer (Geoffroy),Diprion pini (L.) andGilpinia pallida (Klug) were studied in field experiments around a factory complex in southwestern Finland. Larval colonies were transferred
on the shoots of Scots pines growing at different distances from the emission source. Larval mortality was highest near the
factories. InN. sertifer, larval mortality caused by the nuclear polyhedrosis virus was higher and cocoon mortality caused by parasitoids was lower
near the pollutant source. The most abundant parasitoid species wereSynomelix scutulata (Hartig) andLamachus eques (Hartig). 16–67% of theN. sertifer, 0–5% of theD. pini and the 73–100% ofG. pallida cocoons contained parasitoids oviposited during the larval period of the sawflies.
相似文献
16.
Thurm Ulrich Brinkmann Martin Golz Rainer Holtmann Matthias Oliver Dominik Sieger Thiemo 《Hydrobiologia》2004,530(1-3):97-105
Mechanoelectric transduction and its ultrastuctural basis were studied in the cnidocil apparatus of stenotele nematocytes
of marine and freshwater Hydrozoa (Capitata and Hydra) as a paradigm for invertebrate hair cells with concentric hair bundles. The nematocytes respond to selective deflection of their cnidocil with phasic-tonic receptor currents and potentials,
similar to vertebrate hair cells but without directional dependence of sensitivity. Ultrastructural studies and the use of
monoclonal antibodies allowed correlating the mechanoelectric transduction with structural components of the hair bundle.
Two other types of depolarising current and voltage changes in nematocytes are postsynaptic, as concluded from their ionic and pharmacological characteristics. One of these types is induced by mechanical stimulation
of distant nematocytes and sensory hair cells. It is graded in amplitude and duration, but different from the presynaptic receptor potential.
Adequate chemical stimulation of the stenoteles strongly increases the probability of discharge of their cnidocyst, if the
chemical stimulus precedes the mechanical one. Simultaneously, the probability of synaptic signalling induced by mechanical
stimulation is increased, reaching nearly 100%. The chemoreception of the phospholipids used could be localized in the shaft
of the cnidocil, because of the water-insolubility of the stimulant. This chemical stimulation itself does not cause a receptor
potential; its action is classified as a modulatory process. Electron microscopy of serial sections of the tentacular spheres
of Coryne revealed synapses that are efferent to nematocytes and hair cells besides neurite–neurite synapses, each containing 3–10 clear and/or dense-core vesicles of
70–150 nm diameter. The only candidates to explain the graded afferent signal transmission of nematocytes and hair cells are regularly occurring cell contacts associated with 1(–4) clear vesicles
of 160–1100 nm diameter. Transient fusion and partial depletion of stationary vesicles are discussed as mechanisms to reconcile functional and structural data of many cnidarian synapses.
Review contributed to the Symposium on Neuro-Anatomy and -Physiology of Coelenterates; 7th International Conference on Coelenterate
Biology, Lawrence, Kansas, USA; July 6–11, 2003. 相似文献
17.
Chinese Cupressus L. includes five species. The molecular phylogenetic relationship of the Cupressus species and Chamaecyparis L. were determined by comparing 417–479 bp of chloroplast petG-trnP intergenic spacer sequence. In PAUP* analysis, Platycladus orientalis was used as the functional out group. By using the maximum likelihood method 1 077 trees were examined and the result showed
that one tree had a best score of -Ln=2 232.47. The phylogenetic tree clearly showed that Chamaecyparis nootkatensis was diverged from other Chamaecyparis species. Based on the results, together with evidences from other aspects, we consider that Cupressus funebris and Chamaecyparis nootkatensis should be placed in the genus Cupressus. The use of cpDNA intergenic spacer petG-trnP in Cupressus was also discussed.
__________
Translated from Journal of Sichuan University (Natural Science Edition), 2005, 42(5): 1033–1037 [译自: 四川大学学报 (自然科学版) 2005, 42(5): 1033–1037] 相似文献
18.
Mycorrhization helper bacteria (MHB), isolated from phylogenetically distinct ectomycorrhizal symbioses involving Lactarius rufus, Laccaria bicolor or Suillus luteus, were tested for fungus specificity to enhance L. rufus–Pinus sylvestris or L. bicolor–P. sylvestris mycorrhiza formation. As MHB isolated from the L. rufus and S. luteus mycorrhiza were originally characterised using a microcosm system, we assessed their ability to enhance mycorrhiza formation in a glasshouse system in order to determine the extent to which MHB are system-specific. Paenibacillus sp. EJP73, an MHB for L. rufus in the microcosm, significantly enhanced L. bicolor mycorrhiza formation in the glasshouse, demonstrating that the MHB effect of this bacterium is neither fungus-specific nor limited to the original experimental system. Although the five MHB strains studied were unable to significantly enhance L. rufus mycorrhiza formation, two of them did have a significant effect on dichotomous short root branching by L. rufus. The effect was specific to Paenibacillus sp. EJP73 and Burkholderia sp. EJP67, the two strains isolated from L. rufus mycorrhiza, and was not associated with auxin production. Altered mycorrhiza architecture rather than absolute number of mycorrhizal roots may be an important previously overlooked parameter for defining MHB effects. 相似文献
19.
Body proportions,microhabitat selection,and adaptive radiation of Liolaemus lizards in central Chile
Summary A biometric analysis of body proportions with presumably functional meaning for microhabitat selection was made on 12 species of Liolaemus lizards in central Chile. Characters studied were forelimb length, hindlimb length, tail length (all standardized by the corresponding snout-vent length), and the ratio forelimb/hindlimb length. It is shown that irrespective of terrestrial, saxicolous, or arboreal habits, Liolaemus species are remarkably similar in body proportions. The only exceptions are: L. lemniscatus, an open ground-dweller which exhibits significantly shorter limbs; and L. chiliensis and L. schroederi, both shrub-climbers which exhibit significantly longer tail. It is concluded that the adaptive radiation of Liolaemus lizards in central Chile has been accomplished mainly by diversification of activity time, food size, and microhabitat type. Morphological divergence in body proportions seems to have played an unimportant role. 相似文献
20.
To estimate the age and growth of dominant lanternfishes in the Kuroshio–Oyashio Transition Zone, we examined the sagittal
otolith microstructure of Symbolophorus californiensis (n = 30) and Ceratoscopelus warmingii (n = 93) collected from the western North Pacific during 1997–2003. Age of S. californiensis ranged from 81 to 541 days corresponding to postmetamorphosis stage (juveniles and adults), and the von Bertalanffy model
was fitted: L
t
= 128[1 − exp{−0.003(t − 1.52)}], where L is the standard length (mm) and t is age in days. Age of C. warmingii ranged from 6 to 416 days, and growth before metamorphosis was linear (L
t
= 0.346t + 1.51), and the von Bertalanffy model was fitted to the postmetamorphosis stage: L
t
= 80.8 [1 − exp{−0.00769(t − 34.4)}]. Growth of these two lanternfishes was faster than that of other lanternfishes in previous studies but considerably
slower than that of Japanese sardine (Sardinops melanostictus) and anchovy (Engraulis japonicus) distributed in the Kuroshio–Oyashio Transition Zone. Temperature and prey availability are discussed in relation to this
difference in growth rate. 相似文献