scholarly journals The eggshell structure in apteryx ; form, function, and adaptation

2021 ◽  
Author(s):  
David Vieco‐Galvez ◽  
Isabel Castro ◽  
Patrick C. H. Morel ◽  
Wei Hang Chua ◽  
Michael Loh
Keyword(s):  
Form Function ◽  
Eggshell Structure

scholarly journals Eggshell structure in Apteryx: Form, Function, and Adaptation

2020 ◽  
Author(s):  
David Vieco Galvez ◽  
Isabel Castro ◽  
Patrick Morel ◽  
Wei Chua ◽  
Michael Loh
Keyword(s):  
Form Function ◽  
Eggshell Structure

scholarly journals The formation of a hatching line in the serosal cuticle confers multifaceted adaptive functions on the eggshell of a cicada

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Minoru Moriyama ◽  
Kouji Yasuyama ◽  
Hideharu Numata
Keyword(s):  
Protective Role ◽  
Terminal Phase ◽  
Embryonic Diapause ◽  
Insect Eggs ◽  
Ridge Structure ◽  
Conflicting Demands ◽  
Partial Degradation ◽  
Egg Period ◽  
Eggshell Structure

AbstractInsect eggshells must meet various demands of developing embryos. These demands sometimes conflict with each other; therefore, there are tradeoffs between eggshell properties, such as robustness and permeability. To meet these conflicting demands, particular eggshell structures have evolved in diverse insect species. Here, we report a rare eggshell structure found in the eggshell of a cicada, Cryptotympana facialis. This species has a prolonged egg period with embryonic diapause and a trait of humidity-inducible hatching, which would impose severe demands on the eggshell. We found that in eggs of this species, unlike many other insect eggs, a dedicated cleavage site, known as a hatching line, was formed not in the chorion but in the serosal cuticle. The hatching line was composed of a fine furrow accompanied by ridges on both sides. This furrow-ridge structure formed in the terminal phase of embryogenesis through the partial degradation of an initially thick and nearly flat cuticle layer. We showed that the permeability of the eggshell was low in the diapause stage, when the cuticle was thick, and increased with degradation of the serosal cuticle. We also demonstrated that the force required to cleave the eggshell was reduced after the formation of the hatching line. These results suggest that the establishment of the hatching line on the serosal cuticle enables flexible modification of eggshell properties during embryogenesis, and we predict that it is an adaptation to maximize the protective role of the shell during the long egg period while reducing the barrier to emerging nymphs at the time of hatching.

scholarly journals Constraints on the ecomorphological convergence of zooplanktivorous butterflyfishes

2021 ◽  
Author(s):  
Jennifer R Hodge ◽  
Yutong Song ◽  
Molly A Wightman ◽  
Analisa Milkey ◽  
Binh Tran ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Swimming Performance ◽  
Morphological Evolution ◽  
Distinct Type ◽  
Ancestral State ◽  
Multiple Traits ◽  
Visual Identification ◽  
Form Function ◽  
Morphological Distinction ◽  
Foraging Modes

Abstract Whether distantly related organisms evolve similar strategies to meet the demands of a shared ecological niche depends on their evolutionary history and the nature of form-function relationships. In fishes, the visual identification and consumption of microscopic zooplankters, selective zooplanktivory, is a distinct type of foraging often associated with a suite of morphological specialisations. Previous work has identified inconsistencies in the trajectory and magnitude of morphological change following transitions to selective zooplanktivory, alluding to the diversity and importance of ancestral effects. Here we investigate whether transitions to selective zooplanktivory have influenced the morphological evolution of marine butterflyfishes (family Chaetodontidae), a group of small-prey specialists well known for several types of high-precision benthivory. Using Bayesian ancestral state estimation, we inferred the recent evolution of zooplanktivory among benthivorous ancestors that hunted small invertebrates and browsed by picking or scraping coral polyps. Traits related to the capture of prey appear to be functionally versatile with little morphological distinction between species with benthivorous and planktivorous foraging modes. In contrast, multiple traits related to prey detection or swimming performance are evolving toward novel, zooplanktivore-specific optima. Despite a relatively short evolutionary history, general morphological indistinctiveness, and evidence of constraint on the evolution of body size, convergent evolution has closed a near significant amount of the morphological distance between zooplanktivorous species. Overall, our findings describe the extent to which the functional demands associated with selective zooplanktivory have led to generalisable morphological features among butterflyfishes and highlight the importance of ancestral effects in shaping patterns of morphological convergence.

Intonazione e significato: l’esempio dell’italiano regionale di Bergamo

2018 ◽  
Vol 69 (1) ◽  
pp. 35-55
Author(s):  
Giorgio Antonioli ◽  
Manuela Caterina Moroni
Keyword(s):  
Conversation Analysis ◽  
Empirical Data ◽  
Speech Act ◽  
Research Project ◽  
Preliminary Results ◽  
Form Function ◽  
Distinctive Type ◽  
Selection Of

Abstract In this paper we present a selection of preliminary results of our research project “Intonation and Meaning”, in which we compare recurrent intonation contours in German and Italian regional varieties. We apply the method of German Interactional Prosody Research (Interaktionale Prosodieforschung), which in turn is based on Conversation Analysis, to a sample of selfcollected empirical data. Our aim is to show the value of intonation as a resource to contextualize speech activities and to point out form-function relationships between intonation patterns and speech act types. In this respect, we observe the usage of intonation contours with rising accent (L*H) and with falling accent (H*L) in the utterance of question activities, and provide evidence for the fact that the latter represent a distinctive type of questions with epistemic presupposition, whereas L*H correlates rather with default, modally unmarked questions.

Re-engineering Colles: Form, function and fragility fractures

The Surgeon ◽  
2006 ◽  
Vol 4 (1) ◽  
pp. 39-44 ◽  
Author(s):  
T.C. Lee
Keyword(s):  
Fragility Fractures ◽  
Form Function

Eggshell structure, mode of development and growth rate in birds

Zoology ◽  
2008 ◽  
Vol 111 (6) ◽  
pp. 494-502 ◽  
Author(s):  
Ola Karlsson ◽  
Clas Lilja
Keyword(s):  
Growth Rate ◽  
Mode Of Development ◽  
Eggshell Structure

scholarly journals Form-function relations in cone-tipped stimulating microelectrodes

2009 ◽  
Vol 2 ◽  
Author(s):  
Steve Yaeli
Keyword(s):  
Form Function
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