Process and Pattern in Cladonia Subcervicornis

1992 ◽  
Vol 30 (6) ◽  
pp. 567-576 ◽  
Author(s):  
Samuel Hammer
Keyword(s):  
Growth Pattern ◽  
Developmental Stages ◽  
Early Ontogeny ◽  
Non Linear ◽  
Mature Thallus

AbstractMorphogenesis of podetia in Cladonia subcervicornis is a non-linear, repeating process based upon a pattern of meristem enlargement and division. Variability in mature podetia of C. subcervicornis, which may appear branched or scyphoid, is the result of variation early in ontogeny. The growth pattern of C. subcervicornis represents a continuum of developmental stages. It is impossible to predict the form of the mature thallus of C. subcervicornis because growth in this species is fluid. The morphology of the mature thallus of C. subcervicornis is difficult to circumscribe using conventional Cladonia terminology, because the processes that form the thallus are dynamic and heterogeneous. The meristem shapes that are produced during early ontogeny in C. subcervicornis are relatively simple, and the processes by which they are formed are uncomplicated. Yet podetial form in C.subcercicornis is difficult to interpret.

Process and Pattern in Cladonia Subcervicornis.

1998 ◽  
Vol 30 (06) ◽  
pp. 567-576
Author(s):  
Samuel Hammer
Keyword(s):  
Growth Pattern ◽  
Developmental Stages ◽  
Early Ontogeny ◽  
Non Linear ◽  
Mature Thallus

AbstractMorphogenesis of podetia inCladonia subcervicornisis a non-linear, repeating process based upon a pattern of meristem enlargement and division. Variability in mature podetia ofC. subcervicornis, which may appear branched or scyphoid, is the result of variation early in ontogeny. The growth pattern ofC. subcervicornisrepresents a continuum of developmental stages. It is impossible to predict the form of the mature thallus ofC. subcervicornisbecause growth in this species is fluid. The morphology of the mature thallus ofC. subcervicornisis difficult to circumscribe using conventionalCladoniaterminology, because the processes that form the thallus are dynamic and heterogeneous. The meristem shapes that are produced during early ontogeny inC. subcervicornisare relatively simple, and the processes by which they are formed are uncomplicated. Yet podetial form inC.subcercicornisis difficult to interpret.

scholarly journals Wave growth patterns in a non-linear dispersive system with instability and dissipation

1997 ◽  
Vol 20 (3) ◽  
pp. 599-604
Author(s):  
Dinesh Gera ◽  
Mridul Gautam ◽  
Hota V. S. Gangarao
Keyword(s):  
Periodic Solution ◽  
Growth Pattern ◽  
Initial Conditions ◽  
Growth Patterns ◽  
Dispersive Equation ◽  
Time Intervals ◽  
One Dimensional ◽  
Non Linear Equation ◽  
Dispersive System ◽  
Non Linear

A simple one-dimensional non linear equation including effects of instability, dissipation, and dispersion is examined numerically. Periodic solution of a non linear dispersive equation is presented for different values ofα,β, andγcharacterizing the constants for instability, dissipation, and dispersion respectively. In this paper, the growth pattern for the wave at different time intervals is discussed. Various equilibrium states with different initial configuration have been observed depending on initial conditions.

Early development of the Australian crimson-spotted rainbowfish, Melanotaenia fluviatilis (Pisces: Melanotaeniidae)

1995 ◽  
Vol 46 (2) ◽  
pp. 475 ◽  
Author(s):  
HP Reid ◽  
DA Holdway
Keyword(s):  
Developmental Stages ◽  
Water Layer ◽  
Early Ontogeny ◽  
Swim Bladder ◽  
Surrogate Species ◽  
Modifying Factors ◽  
Factors Influencing ◽  
The Mean ◽  
Australian Freshwater ◽  
The Impact

This paper describes the early ontogeny of the crimson-spotted rainbowfish Melanotaenia fluviatilis. Eggs ranged in size from 0.98 to 1.07 mm and 35-45 oil droplets were present, as were numerous adhesive filaments which originated from one point. Hatching was predominantly 7-9 days after spawning at 25.5�C. At hatching, larvae (4.2 mm standard length) had a reduced but still present yolk sac and were strong enough swimmers to remain in the upper 1 cm water layer. The swim bladder inflated within 10 h of hatching and the first ingested food was observed after 12 h. At 32 days after hatching, the mean larval length was 13.86 rnm and at 72 days was 21 mm. Knowledge of the critical developmental stages described in the paper is important in understanding the impact of the major biotic modifying factors influencing the impact of chemicals and other pollutants on rainbowfish, especially given that they are used by ecotoxicologists as a surrogate species for Australian freshwater fish in general.

scholarly journals Comparing two versions of a non-linear model for simulating leaf number and developmental stages in maize based on air temperature

2008 ◽  
Vol 39 (3) ◽  
pp. 642-648 ◽  
Author(s):  
Nereu Augusto Streck ◽  
Luana Fernandes Gabriel ◽  
Flavia Kaufmann Samboranha ◽  
Isabel Lago ◽  
Ana Paula Schwantes ◽  
...  
Keyword(s):  
Air Temperature ◽  
Developmental Stages ◽  
Temperature Response ◽  
Growing Season ◽  
Leaf Number ◽  
Physiological Maturity ◽  
Arithmetic Average ◽  
Daily Minimum ◽  
Maize Variety ◽  
Non Linear

The Wang and Engel (WE) model simulates crop development considering the non-linear response of plant development to temperature. Daily air temperature is the input for the temperature response function [f(T)] in the WE model, and because there are several approaches for computing daily temperatures, there are several ways to calculate the f(T). The objective of this study was to compare two versions of the WE model for simulating leaf number and developmental stages in maize, considering two approaches for imputing daily air temperature (daily mean air temperature and daily minimum/maximum air temperature). A two-year field experiment with the maize variety BRS Missões sown in several sowing dates was conducted in Santa Maria, Rio Grande do Sul State, Brazil, during the 2005-2006 and 2006-2007 growing seasons. The f(T) in the WE model was calculated using daily mean air temperature calculated as the arithmetic average of daily minimum (TN) and maximum (TX) air temperatures (WE Tmean), and calculating an f(T) using TN and an f(T) using TX and then averaging the two f(T)s (WE Tmm). Ligule and tip leaf number, and silking and physiological maturity developmental stages measured in the 2005-2006 growing season were used to estimate model coefficients and the ones measured in the 2006-2007 growing season were used as independent data sets to evaluate models. Predictions of ligule and tip leaf number, silking and physiological maturity of the maize variety BRS Missões were better with the WE Tmm model than with the WE Tmean model.

Developmental and growth patterns in Xiphinema parasimile and X. simile (Nematoda: Dorylaimida), members of the X. americanum-group

Nematology ◽  
2009 ◽  
Vol 11 (2) ◽  
pp. 267-273
Author(s):  
László Barsi
Keyword(s):  
Body Length ◽  
Growth Pattern ◽  
Developmental Stages ◽  
Growth Patterns ◽  
Body Volume ◽  
Data Sets ◽  
Embryonic Growth ◽  
Juvenile Stages ◽  
The Mean ◽  
The Difference

AbstractXiphinema parasimile and X. simile are morphologically and morphometrically very similar, yet molecularly different, species with different developmental and growth patterns, a different number of juvenile developmental stages (four vs three) and a different post-embryonic growth pattern. Body length, body volume and odontostyle and replacement odontostyle lengths served for comparison of the post-embryonic growth patterns in these species. A percentage method was used to make the data sets comparable between one population of X. parasimile and three populations of X. simile. The mean body lengths of the first, second and pre-adult stages in X. simile showed similarity with those of the second, third and pre-adult stages in X. parasimile. In X. simile there was no unique growth pattern of body length and body volume from stage to stage applicable for all populations, just a similar trend with more or less similar values. The difference between replacement odontostyle and functional odontostyle lengths in all juvenile stages was higher in X. simile and lower in X. parasimile, despite the very similar mean odontostyle length in the female stage of both species.

scholarly journals Effects of Experimental Ocean Acidification on the Larval Morphology and Metabolism of a Temperate Sparid, Chrysoblephus laticeps

Oceans ◽  
2020 ◽  
Vol 2 (1) ◽  
pp. 26-40
Author(s):  
Cuen Muller ◽  
Amber-Robyn Childs ◽  
Nicola C. James ◽  
Warren M. Potts
Keyword(s):  
Oxygen Consumption ◽  
Ocean Acidification ◽  
Developmental Stages ◽  
Fish Larvae ◽  
Marine Species ◽  
Early Ontogeny ◽  
Early Life Stages ◽  
Lower Growth ◽  
Growth Metrics ◽  
Commercially Important

Ocean acidification is predicted to have widespread impacts on marine species. The early life stages of fishes, being particularly sensitive to environmental deviations, represent a critical bottleneck to recruitment. We investigated the effects of ocean acidification (∆pH = −0.4) on the oxygen consumption and morphometry during the early ontogeny of a commercially important seabream, Chrysoblephus laticeps, up until flexion. Hatchlings appeared to be tolerant to hypercapnic conditions, exhibiting no difference in oxygen consumption or morphometry between treatments, although the yolk reserves were marginally reduced in the low-pH treatment. The preflexion stages appeared to undergo metabolic depression, exhibiting lower metabolic rates along with lower growth metrics in hypercapnic conditions. However, although the sample sizes were low, the flexion-stage larvae exhibited greater rates of metabolic and growth metric increases in hypercapnic conditions. This study shows that the effects of OA may be stage specific during early ontogeny and potentially related to the development of crucial organs, such as the gills. Future studies investigating the effects of climate change on fish larvae should endeavour to include multiple developmental stages in order to make more accurate predictions on recruitment dynamics for the coming decades.

scholarly journals A fast-growing basal troodontid (Dinosauria: Theropoda) from the latest Cretaceous of Europe

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Albert G. Sellés ◽  
Bernat Vila ◽  
Stephen L. Brusatte ◽  
Philip J. Currie ◽  
Àngel Galobart
Keyword(s):  
Growth Pattern ◽  
Mass Extinction ◽  
New Genus ◽  
Phylogenetic Analyses ◽  
Early Ontogeny ◽  
Bone Histology ◽  
New Genus And Species ◽  
Fast Growing ◽  
Theropod Dinosaurs ◽  
Dispersal Events

AbstractA characteristic fauna of dinosaurs and other vertebrates inhabited the end-Cretaceous European archipelago, some of which were dwarves or had other unusual features likely related to their insular habitats. Little is known, however, about the contemporary theropod dinosaurs, as they are represented mostly by teeth or other fragmentary fossils. A new isolated theropod metatarsal II, from the latest Maastrichtian of Spain (within 200,000 years of the mass extinction) may represent a jinfengopterygine troodontid, the first reported from Europe. Comparisons with other theropods and phylogenetic analyses reveal an autapomorphic foramen that distinguishes it from all other troodontids, supporting its identification as a new genus and species, Tamarro insperatus. Bone histology shows that it was an actively growing subadult when it died but may have had a growth pattern in which it grew rapidly in early ontogeny and attained a subadult size quickly. We hypothesize that it could have migrated from Asia to reach the Ibero-Armorican island no later than Cenomanian or during the Maastrichtian dispersal events.

scholarly journals Positional specification in the segmental growth pattern of an early arthropod

2014 ◽  
Vol 281 (1781) ◽  
pp. 20133037 ◽  
Author(s):  
Giuseppe Fusco ◽  
Paul S. Hong ◽  
Nigel C. Hughes
Keyword(s):  
Growth Pattern ◽  
Developmental Stages ◽  
Growth Models ◽  
Regional Growth ◽  
Growth Control ◽  
Growth Dynamics ◽  
Main Body ◽  
Differential Growth ◽  
Continuous Growth ◽  
Complex Forms

In many arthropods, there is a change in relative segment size during post-embryonic development, but how segment differential growth is produced is little known. A new dataset of the highest quality specimens of the 429 Myr old trilobite Aulacopleura koninckii provides an unparalleled opportunity to investigate segment growth dynamics and its control in an early arthropod. Morphometric analysis across nine post-embryonic stages revealed a growth gradient in the trunk of A. koninckii . We contrastively tested different growth models referable to two distinct hypotheses of growth control for the developing trunk: (i) a segment-specific control, with individual segments having differential autonomous growth progression, and (ii) a regional control, with segment growth depending on their relative position along the main axis. We show that the trunk growth pattern of A. koninckii was consistent with a regional growth control producing a continuous growth gradient that was stable across all developmental stages investigated. The specific posterior-to-anterior decaying shape of the growth gradient suggests it deriving from the linear transduction of a graded signal, similar to those commonly provided by morphogens. A growth control depending on a form of positional specification, possibly realized through the linear interpretation of a graded signal, may represent the primitive condition for arthropod differential growth along the main body axis, from which the diverse and generally more complex forms of growth control in subsequent arthropods have evolved.

scholarly journals Comparison of Non-Linear Models to Describe of Growth Pattern in Makuie Sheep

2020 ◽  
Vol 11 (27) ◽  
pp. 88-94
Author(s):  
mahdi nezhadali ◽  
sadegh alijani ◽  
Arash javanmard ◽  
◽  
◽  
...  
Keyword(s):  
Growth Pattern ◽  
Linear Models ◽  
Non Linear
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