Search results for "Von bertalanffy"
showing 5 items of 5 documents
Growth patterns and life-history strategies in Placodontia (Diapsida: Sauropterygia)
2015
Placodontia is a clade of durophagous, near shore marine reptiles from Triassic sediments of modern-day Europe, Middle East and China. Although much is known about their primary anatomy and palaeoecology, relatively little has been published regarding their life history, i.e. ageing, maturation and growth. Here, growth records derived from long bone histological data of placodont individuals are described and modelled to assess placodont growth and life-history strategies. Growth modelling methods are used to confirm traits documented in the growth record (age at onset of sexual maturity, age when asymptotic length was achieved, age at death, maximum longevity) and also to estimate undocum…
Heikko ravintotilanne rajoittaa hauen (Esox lucius) ja kuhan (Sander lucioperca) kasvua Suotajärvessä
2014
Hauki ja kuha esiintyvät Suomessa usein samoissa vesistöissä, mutta niiden vuorovaikutuksesta tiedetään vain vähän. Mikäli lajit kilpailevat samoista resursseista, runsaat kuhaistutukset tai kuhan luonnollinen yleistyminen voivat vaikuttaa negatiivisesti hauen menestykseen. Tämän tutkimuksen tarkoitus oli selvittää hauen ja kuhan kasvua ja ravinnonkäyttöä Suotajärvessä. Kasvua tarkasteltiin myös suhteessa kasvukausien lämpötilaan. Ravinnonkäytössä keskityttiin hauen ja kuhan ravinnon päällekkäisyyteen ja siitä mahdollisesti seuraavaan ravintokilpailuun. Lisäksi verkkokoekalastuksilla selvitettiin järven kalaston yleistä tilaa, erityisesti ajatellen petokalojen ravintotilannetta. Hauki- ja k…
Theoretical Biology and Evolutionary Theory
2015
During the nineteen-sixties and seventies, several biologists made decisive contributions to the development of evolutionary thought and theoretical biology, smoothly bridging the gap between science and humanities, and overcoming the classic antagonism Snow claimed to exist between the two worlds. Scientists like Jacob , Lorenz , Monod , Rensch , von Bertalanffy or Waddington , to whom I pay homage here, are a select group of scientists pertaining to the so-called third culture, who have staged a scientific assault on Natural Philosophy—the forerunners of subsequent science popularisers such as Dawkins , Gould , Penrose , Gell-Mann or Pinker . Finally I call for a more detailed study of th…
Study of Pinna nobilis growth from inner record: How biased are posterior adductor muscle scars estimates?
2011
abstract Article history:Received 14 June 2011Received in revised form 19 July 2011Accepted 20 July 2011Available online 17 August 2011Keywords:BivalviaEndangered speciesMediterraneanSclerochronologySpain Previous studies have shown that the external growth records of the posterior adductor muscle scar (PAMS)ofthe bivalve Pinna nobilisareincomplete and donot produce accurate ageestimations. We havedeveloped anew methodology to study age and growth using the inner record of the PAMS, which avoids the necessity ofcostly in situ shell measurements or isotopic studies. Using the inner record we identified the positions ofPAMS previously obscured by nacre and estimated the number of missing recor…
Empirical links between natural mortality and recovery in marine fishes
2017
Probability of species recovery is thought to be correlated with specific aspects of organismal life history, such as age at maturity and longevity, and how these affect rates of natural mortality ( M ) and maximum per capita population growth ( r max ). Despite strong theoretical underpinnings, these correlates have been based on predicted rather than realized population trajectories following threat mitigation. Here, we examine the level of empirical support for postulated links between a suite of life-history traits (related to maturity, age, size and growth) and recovery in marine fishes. Following threat mitigation (medium time since cessation of overfishing = 20 years), 71% of 55 tem…