Adaptation and evolution in Gallotia lizards from the Canary Islands: age, growth, maturity and longevity

1991 ◽  
Vol 12 (1) ◽  
pp. 81-102 ◽  
Author(s):  
Jacques Castanet ◽  
Marcos Baez

AbstractQualitative and quantitative comparisons of histological data recorded from growing bone from seven extant and extinct taxa of Gallotia show that these lizards do not have the same longevity, reach sexual maturity at various ages and probably have different growth rates which are in reverse proportion to the specific size of individuals in each taxon. In term of relative growth, the highest rate is seen in the smallest taxon (G. atlantica) and the lowest in the largest taxon (G. goliath). It appears that differences between the maximum size reached, irrespective of the size of hatchlings, are only the consequence of changes in longevity allowing a more or less protracted growth; they are not due to differences in growth rates. On the basis of these data we discuss some points relating to adaptive strategies and evolutionary features of these lizards.

1970 ◽  
Vol 27 (12) ◽  
pp. 2155-2158 ◽  
Author(s):  
G. P. Ennis

In Newfoundland waters, shorthorn sculpins, Myoxocephalus scorpius (L.), live to age 15 and attain a maximum size of just over 50 cm. The growth rates of males and females are little different below age 4, but above age 4 the females grow faster than the males, and the difference between average length-at-age for males and females gets progressively larger with age. Males mature at a younger age and at a smaller size than females. In any age-group where there are mature and immature individuals the mature ones are larger.


1996 ◽  
Vol 26 (9) ◽  
pp. 1556-1568 ◽  
Author(s):  
Thimmappa S. Anekonda ◽  
Richard S. Criddle ◽  
Lee D. Hansen ◽  
Mike Bacca

Seventeen Eucalyptus species and 30 rapid-growing Eucalyptuscamaldulensis trees (referred to as plus trees), growing in a plantation were studied to examine relationships among measured plant growth and respiratory parameters, geographical origins, and growth climate. The respiratory parameters measured at two different temperatures by isothermal calorimetry were metabolic heat rate, rate of CO2 production, and the ratio of heat rate to CO2 rate. Metabolic heat rate was also measured as a continuous function of temperature by differential scanning calorimetry in the range of 10 to 40 °C. Tree growth was measured as rates of height and stem volume growth. The values of respiratory and growth variables of Eucalyptus species are significantly correlated with latitude and altitude of origin of their seed sources. The maximum metabolic heat rate, the temperature of the maximum heat rate, the temperature coefficients of metabolic rate, and the temperatures at which the slopes of Arrhenius plots change are all genetically determined parameters that vary both within and among species. Measurement of growth rate–respiration rate–temperature relationships guide understanding of why relative growth rates of Eucalyptus species and individual genotypes differ with climate, making it possible to identify genotypes best suited for rapid growth in different climates. The temperature dependence of respiration rates is an important factor determining relative growth rates of eucalypts in different climates. To achieve optimum biomass production the temperature dependence of individual plants must be matched to growth climate.


1967 ◽  
Vol 69 (3) ◽  
pp. 305-315 ◽  
Author(s):  
J. E. Jackson

Growth analysis of cotton crops sown in the Sudan Gezira at monthly intervals between August and May revealed a marked seasonal pattern of growth. Irrespective of plant age and fruiting state growth of non-senescent plants was slowest during the cool winter months. Relative growth rates of young plants were highest in August, September and early October due to the high specific leaf areas and fairly high net assimilation rates found then. They were lowest when minimum temperatures were lowest. Net assimilation rates were also lowest in the coolest months, probably as a result of restricted growth. High temperatures in the spring reduced fruiting. It is concluded that low minimum temperatures and high evaporation rates are both associated with slow growth, and play a large part in determining the characteristic decline of growth rates of cotton sown at the usual date in August.I wish to thank the Chief of the Research Division, Ministry of Agriculture, Sudan, for permission to publish this paper and to record my gratitude to the team of field and laboratory assistants, especially Salih Saad and Hassan Osman, who helped in the work.


2015 ◽  
Vol 37 (1) ◽  
pp. 73-88
Author(s):  
Petra Baji ◽  
Márta Péntek ◽  
Imre Boncz ◽  
Valentin Brodszky ◽  
Olga Loblova ◽  
...  

In the past few years, several papers have been published in the international literature on the impact of the economic crisis on health and health care. However, there is limited knowledge on this topic regarding the Central and Eastern European (CEE) countries. The main aims of this study are to examine the effect of the financial crisis on health care spending in four CEE countries (the Czech Republic, Hungary, Poland and Slovakia) in comparison with the OECD countries. In this paper we also revised the literature for economic crisis related impact on health and health care system in these countries. OECD data released in 2012 were used to examine the differences in growth rates before and after the financial crisis. We examined the ratio of the average yearly growth rates of health expenditure expressed in USD (PPP) between 2008–2010 and 2000–2008. The classification of the OECD countries regarding “development” and “relative growth” resulted in four clusters. A large diversity of “relative growth” was observed across the countries in austerity conditions, however the changes significantly correlate with the average drop of GDP from 2008 to 2010. To conclude, it is difficult to capture visible evidence regarding the impact of the recession on the health and health care systems in the CEE countries due to the absence of the necessary data. For the same reason, governments in this region might have a limited capability to minimize the possible negative effects of the recession on health and health care systems.


2007 ◽  
Vol 50 (2) ◽  
pp. 259-267 ◽  
Author(s):  
Giovana Bertini ◽  
Adriane Araújo Braga ◽  
Adilson Fransozo ◽  
Michéle de Oliveira Dias Alves Corrêa ◽  
Fulvio Aurélio de Morais Freire

The relative growth and size at onset of morphological sexual maturity of the stone crab Menippe nodifrons were investigated. A total of 399 crabs was captured on Praia Grande and Tenório beaches at Ubatuba. Carapace width (CW) and length, cheliped propodus length and height, abdomen width in females, and gonopod length in males were recorded. In females, the abdominal width showed negative allometry for juveniles and positive allometry for adults; the puberty molt occurred at 31.6 mm CW. In males, the size at onset of morphological sexual maturity was estimated as 29.7 mm CW; the gonopod growth showed positive allometry for juveniles, and an isometric relationship for adults. The gonopod length and the abdominal width were the most appropriate morphometric variables to estimate size at onset of sexual maturity in this stone crab.


1989 ◽  
Vol 40 (2) ◽  
pp. 293 ◽  
Author(s):  
DR Eagling ◽  
RJ Sward ◽  
GM Halloran

Measurements were made on the effect of barley yellow dwarf virus (BYDV) infection on the early growth of four commercial cultivars of ryegrass (Lolium spp.) under two different temperatures (24�C and 16�C). At 24'C, BYDV infection was associated with reduced root dry weight (30-40%) in all cultivars; the effect of infection on shoot dry weight and leaf area was variable. At 16�C, the effect of BYDV infection was variable, being associated with increases in root dry weight, shoot dry weight, and leaf area in one cultivar (Grasslands Ariki) and decreases in another (Victorian). In two other cultivars, root dry weight, shoot dry weight and leaf area were not significantly affected (P>0.05) by infection with BYDV.At 24�C, the reductions in root dry weight associated with BYDV infection were not concomitant with reductions in the root relative growth rates. Up to at least 28 days after inoculation (46-50 days after germination) reductions in root dry weight were associated with both aphid-feeding damage and virus infection. Experiments with the cultivar Victorian, showed that shoot dry weight was not significantly affected (P>0.05) by feeding with viruliferous (BYDV) or non-viruliferous aphids (Rhopalosiphum padi L.). At 16�C, changes in root and shoot dry weight were associated with changes in the root and shoot relative growth rates.


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