scholarly journals Behavioural response to songs between genetically diverged allopatric populations of Darwin’s small tree finch in the Galápagos

2021 ◽  
Author(s):  
Diane Colombelli‐Négrel ◽  
Sonia Kleindorfer
Keyword(s):  
Behavioural Response ◽  
Small Tree ◽  
Allopatric Populations

Propagation of Alnus maritima [Marsh.] Nutt. (Seaside Alder)

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 479b-479
Author(s):  
James A. Schrader ◽  
William R. Graves
Keyword(s):  
Delmarva Peninsula ◽  
Small Tree ◽  
South Central ◽  
Disjunct Populations ◽  
Rooting Of Cuttings ◽  
Sexual Propagation ◽  
Managed Landscapes ◽  
Time Of Collection ◽  
Over Time ◽  
Seaside Alder

We are interested in the potential of seaside alder as a shrub or small tree for managed landscapes. This species has received little attention from horticulturists and occurs naturally only in small, disjunct populations in Maryland and southern Delaware (Delmarva Peninsula), northwestern Georgia, and south-central Oklahoma. Our objective is to optimize asexual (softwood cuttings and tissue culture) and sexual propagation of seaside alder while testing for differences in propagation success among populations. Terminal softwood cuttings collected 11 June 1997 (Delmarva) and 25 Aug. 1997 (Oklahoma) were treated with IBA at various concentrations and provided intermittent mist in a greenhouse for 10 weeks. Up to 44% rooting was achieved by using 1 g IBA/kg on cuttings from Delmarva; replication over time will be used to determine whether poorer rooting of cuttings from Oklahoma (maximum of 17% with 8 g IBA/kg) was due to genotypic effects or the time of collection. Strobili were collected during late 1997 from multiple plants in the three populations. Unstratified seed from Oklahoma showed from 40% to 76% germination after 21 days depending on the tree of origin. The only previous data of germination of unstratified seeds was a report of 5% to 20% for seeds from Delmarva, so provenance as well as stratification effects on germination are being evaluated.

scholarly journals Empirical study of spatial differentiation of youth unemployment in Russia

2016 ◽  
Vol 66 (3) ◽  
pp. 507-526 ◽  
Author(s):  
Tatiana Blinova ◽  
Vladimir Markov ◽  
Viktor Rusanovskiy
Keyword(s):  
Labour Market ◽  
Age Groups ◽  
Spatial Differentiation ◽  
Youth Unemployment ◽  
Behavioural Response ◽  
Economic Effects ◽  
Group Differences ◽  
Unemployment Rates ◽  
Youth Labour Market ◽  
Interregional Differentiation

The purpose of the study is to conduct a statistical analysis and to perform a quantitative assessment of the degree and the dynamics of the interregional differences in youth unemployment in Russia between 2005 and 2013. We decompose the interregional differentiation into “within-group” and “between-group” differences. We also analyse the dynamics of the within-group and between-group differences and estimate their contribution to changes in the interregional differentiation of youth unemployment. Additionally, we estimate the degree and the dynamics of the interregional differences of the youth labour market in Russia in times of crisis and recovery growth. The results show a reduction in the interregional differences in unemployment rates between 2005 and 2008, while in 2009–2013, the interregional differentiation of the labour market increased. We found that the socio-economic effects of youth unemployment, as well as the behavioural response to economic shocks in the age groups of 15–19 and 20–29 years were significantly different.

OESTROGEN-PROGESTERONE RELATIONSHIPS IN THE INDUCTION OF OESTRUS IN SPAYED HEIFERS

1969 ◽  
Vol 45 (1) ◽  
pp. 99-109 ◽  
Author(s):  
M. J. CARRICK ◽  
J. N. SHELTON
Keyword(s):  
Behavioural Response ◽  
Normal Response ◽  
Oestradiol Benzoate ◽  
Small Doses ◽  
Refractory State ◽  
Increased Sensitivity ◽  
Repeated Doses ◽  
Effective Doses ◽  
Response Line ◽  
Normal Sensitivity

SUMMARY Experiments were conducted to examine the behavioural response of spayed heifers to oestrogen, and its modification by progesterone. In two groups of heifers, the median effective doses (MED) of oestradiol benzoate (ODB) were 121 and 132 μg. Repeated doses of ODB at physiological levels did not induce a state of refractoriness; in this respect the heifer is dissimilar to the ewe. However, repeated doses of 10 mg. ODB induced refractoriness to 400 μg. ODB. When such refractory heifers were treated with 10 mg. progesterone/day for 5 days, they showed a normal response to 400 μg. ODB given 3 days later. This return to normal sensitivity was not sustained, and pretreatment with progesterone was necessary for a normal response to subsequent small doses of ODB. The transient removal of the refractory state appears not to be due to a simple synergistic effect of residual progesterone, but to an effect of preconditioning a neural centre to respond to oestrogen. Increasing the duration of pretreatment with progesterone beyond 5 days did not result in a greater sensitivity to ODB. Pretreatment with progesterone in heifers not made refractory to ODB did not result in an increased sensitivity to ODB. Moreover, up to 7 days after termination of the progesterone treatment, the response to ODB was reduced and the slope of the dose-response line was less steep than when ODB was injected alone. The reduction of the response was more pronounced with 40 mg. progesterone/day than with 10 mg. The possible significance of these results in intact animals is discussed.

scholarly journals The dose makes the poison: Non-linear behavioural response to CO2-induced aquatic acidification in zebrafish (Danio rerio)

2021 ◽  
Vol 778 ◽  
pp. 146320
Author(s):  
Trevor J. Hamilton ◽  
Nicole Hurst Radke ◽  
Jasmin Bajwa ◽  
Shayna Chaput ◽  
Martin Tresguerres
Keyword(s):  
Danio Rerio ◽  
Behavioural Response ◽  
Non Linear ◽  
Aquatic Acidification

scholarly journals Generalized olfactory detection of floral volatiles in the highly specialized Greya-Lithophragma nursery pollination system

2021 ◽  
Author(s):  
Florian P. Schiestl ◽  
Erika A. Wallin ◽  
John J. Beck ◽  
Magne Friberg ◽  
John N. Thompson
Keyword(s):  
Selective Advantage ◽  
Floral Volatiles ◽  
Pollination System ◽  
Allopatric Populations ◽  
Evolutionary Scenario ◽  
Plant Recognition ◽  
Hexahydrofarnesyl Acetone ◽  
Electroantennographic Detection ◽  
Local Host ◽  
Olfactory Detection

AbstractVolatiles are of key importance for host-plant recognition in insects. In the pollination system of Lithophragma flowers and Greya moths, moths are highly specialized on Lithophragma, in which they oviposit and thereby pollinate the flowers. Floral volatiles in Lithophragma are highly variable between species and populations, and moths prefer to oviposit into Lithophragma flowers from populations of the local host species. Here we used gas chromatography coupled with electroantennographic detection (GC-EAD) to test whether Greya moths detect specific key volatiles or respond broadly to many volatiles of Lithophragma flowers. We also addressed whether olfactory detection in Greya moths varies across populations, consistent with a co-evolutionary scenario. We analyzed flower volatile samples from three different species and five populations of Lithophragma occurring across a 1400 km range in the Western USA, and their sympatric female Greya politella moths. We showed that Greya politella detect a broad range of Lithophragma volatiles, with a total of 23 compounds being EAD active. We chemically identified 15 of these, including the chiral 6, 10, 14-trimethylpentadecan-2-one (hexahydrofarnesyl acetone), which was not previously detected in Lithophragma. All investigated Lithophragma species produced the (6R, 10R)-enantiomer of this compound. We showed that Greya moths detected not only volatiles of their local Lithophragma plants, but also those from allopatric populations/species that they not encounter in local populations. In conclusion, the generalized detection of volatiles and a lack of co-divergence between volatiles and olfactory detection may be of selective advantage for moths in tracking hosts with rapidly evolving, chemically diverse floral volatiles.

Integrative taxonomic and geographic variation analyses in Cyrtodactylus aequalis (Squamata: Gekkonidae) from southern Myanmar (Burma): one species, two different stories

2020 ◽  
Vol 66 (3-4) ◽  
pp. 151-179
Author(s):  
L. Lee Grismer ◽  
L. Wood Perry ◽  
Marta S. Grismer ◽  
Evan S.H. Quah ◽  
Myint Kyaw Thura ◽  
...  
Keyword(s):  
Geographic Variation ◽  
Evolutionary History ◽  
Phylogenetic Inference ◽  
Morphological Characters ◽  
Molecular Data ◽  
Biodiversity Crisis ◽  
Allopatric Populations ◽  
Compelling Argument ◽  
Historical Accuracy ◽  
Molecular Phylogenetic

The historical accuracy of building taxonomies is improved when they are based on phylogenetic inference (i.e., the resultant classifications are less apt to misrepresent evolutionary history). In fact, taxonomies inferred from statistically significant diagnostic morphological characters in the absence of phylogenetic considerations, can contain non-monophyletic lineages. This is especially true at the species level where small amounts of gene flow may not preclude the evolution of localized adaptions in different geographic areas while underpinning the paraphyletic nature of each population with respect to the other. We illustrate this point by examining genetic and morphological variation among three putatively allopatric populations of the granite-dwelling Bent-toed Gecko Cyrtodactylus aequalis from hilly regions in southeastern Myanmar. In the absence of molecular phylogenetic inference, a compelling argument for three morphologically diagnosable species could be marshaled. However, when basing the morphological analyses of geographic variation on a molecular phylogeny, there is a more compelling argument that only one species should be recognized. We are cognizant of the fact however, that when dealing with rare species or specimens for which no molecular data are possible, judicious morphological analyses are the only option—and the desired option given the current worldwide biodiversity crisis.

scholarly journals Serotonin and Tryptophan Serum Concentrations in Shelter Dogs Showing Different Behavioural Responses to a Potentially Stressful Procedure

2020 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Giacomo Riggio ◽  
Chiara Mariti ◽  
Valeria Sergi ◽  
Silvana Diverio ◽  
Angelo Gazzano
Keyword(s):  
Behavioural Response ◽  
Blood Collection ◽  
Stressful Situation ◽  
Serum Concentrations ◽  
Chi Square ◽  
Significant Difference ◽  
Relaxation Stress ◽  
Shelter Dogs ◽  
Stress Signals ◽  
The Relationship

In mammals, serotonin (5-HT) levels depend on the availability of tryptophan (TRP). Low 5-HT concentrations have been linked to behavioural disorders in dogs. This study aimed at investigating possible differences in dogs’ serum TRP and 5-HT concentrations according to their behavioural response to a potentially stressful procedure. Thirty-nine physically healthy shelter dogs, 15 females and 24 males, mean age = 5.6 years, were categorized by a certified veterinary behaviourist according to their behavioural response to medical examination and blood collection, in: relaxation, stress signals, tension without growling, tension with growling, escape attempts, and aggression attempts. Extraction and quantification of 5-HT and TRP were performed using a HLPC method. Data were statistically analysed, applying Chi-square and Spearman tests. Results showed no significant difference in TRP (χ2 = 2.084, p = 0.555) nor 5-HT (χ2 = 0.972, p = 0.808) serum concentrations among different categories of dogs; however, some categories were underrepresented (relaxation = 20.5%, stress signals = 30.8%, tension without growling = 43.6%, tension with growling = 5.1%, escape attempts = 0%, aggression attempts = 0%). No correlation between serum TRP and 5-HT concentrations was found (ρ = 0.086, p = 0.602). Serum 5-HT levels do not seem to be associated with dogs’ behavioural response to a stressful situation nor with serum TRP concentrations. The relationship between serum TRP and 5-HT concentrations and behaviour needs further research.

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