Journal ArticleDOI
A new graphic method of describing the growth of animals.
TLDR
Growth curves, when conventionally plotted as length on age, are difficult to compare and classify; the usual mathematical methods of fitting them, such as the logistic and the Gompertz are rather laborious and incon venient for application to large numbers of individuals.Abstract:
Growth curves, when conventionally plotted as length on age, are difficult to compare and classify. Moreover, the usual mathematical methods of fitting them, such as, the logistic and the Gompertz are rather laborious and incon venient for application to large numbers of individuals. Fortunately, for many purposes, it is unnecessary to describe the whole growth curve; for the part below the inflection point is completed early and the part above the inflection point—the “? self-inhibiting― phase, covers the period of life when differences in growth are likely to be most striking. That phase of the growth curve can be appropriately represented by a straight line, the charac teristics of which can be treated statistically, by the following graphic method: Using arithmetic graph paper, with body length represented along both the x axis and along the y axis, plot length at ages 1, 2, 3, 4, 5@ n on the x axis against length at ages 2, 3, 4, 5, 6. n + 1, respectively, on the y axis. For several species on which I have found published length data, these points fall along a straight line. This line can be regarded as a sort of transformation of the usual growth curve, and in the following discussion I will call it that. The nine examples given in Figures 1—3are based on average lengths of large samples. When lengths of individual specimens are plotted by this method, a straight-line relationship is still obvious, though the points deviate more widely from the linethan when averages are used. These deviationsdoubtless result from several causes, among which random variations in environmental experience and errors of observation readily suggest themselves. For a few species the published growth data failed to produce a straight line. In these cases, the course of growth may differ from that in other animals; or the observed anomalies may reflect some artifactual effect in the data. Among those species for which this “? transformation― results in a straight line, the growth increments corresponding to equal time intervals, for example, be tween years of age (12 —? 11,13 —? 12,14 —? i@, @l,—? i@), have the following inter relations; where 1,, refers to the length at any given age, i.e., at the end of any given time interval :2read more
Citations
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Journal ArticleDOI
The Growth and Mortality of Four Species of Fish in the River Thames at Reading
TL;DR: This paper results from a series of observations made on fish populations in the River Thames at Reading between October 1958 and October 1959, which forms part of a long-term ecological investigation being carried out in the Caversham-Sonning reach of the river.
Journal ArticleDOI
Mark‐recapture experiments on fish in Windermere, 1943–1982
C. Kipling,E. D. Cren +1 more
TL;DR: Estimates of numbers and mortality were not satisfactory, except for limited sections of the populations of pike and charr and the experiments provided useful information on movements and growth.
Journal ArticleDOI
Age and Growth Determination of the Bat Ray, Myliobatis californica Gill, in Central California
TL;DR: WOURMS, J. P. as discussed by the authors, et al. describe the reproductive condition of elasmobranch fishes in Elkhorn Slough, California and their development in chondrichthyan fishes. Fish Game 71(4):210-229. Accepted 4 Dec. 1987.
Journal ArticleDOI
Are introduced gibel carp Carassius gibelio in Turkey more invasive in artificial than in natural waters
Ali Serhan Tarkan,Gordon H. Copp,Nildeniz Top,N. Özdemi̇r,Bahadir Önsoy,Gökçen Bilge,Halit Filiz,Sercan Yapıcı,Fitnat Güler Ekmekçi,Şerife Gülsün Kirankaya,Özgür Emiroğlu,Özcan Gaygusuz,Ç. Gürsoy Gaygusuz,A. Oymak,Gülnaz Özcan,Gülşah Saç +15 more
TL;DR: With the exception of smaller size at maturity, all traits were higher in populations from artificial water bodies than those inhabiting running waters, suggesting gibel carp is required to exert more reproductive effort to invade natural ecosystems than artificial waters.
Journal ArticleDOI
Production of calcium carbonate on the mainland shelf of southern california1
TL;DR: In this paper, the authors collected data from three localities and 22 stations along the southern California coastline and gave subtidal rates of CaC03 production by calcarcous organisms, from turnover rates calculated from growth rate data, from mortality calculations based on size distribution and growth data, and from miscellaneous information, near 400 g CaCO3 mW2 yr-l.
References
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Book
On Growth and Form
TL;DR: This book is an application of some of the concepts of physical science and sundry mathematical methods to the study of organic form and is like one of Darwin's books, well-considered, patiently wrought-out, learned, and cautious.
Journal ArticleDOI
Latitude and Relative Growth in the Razor Clam, Siliqua Patula
TL;DR: Current mathematical expressions for the course of growth are discussed and a formula used which emphasises Minot's conception of a growth-rate constantly declining with age is found to graduate the extensive data in clam growth with significant accuracy.