Inherency of Form and Function in Animal Development and Evolution

Development and evolution of animal behaviour and morphology are frequently addressed independently, as reflected in the dichotomy of disciplines dedicated to their study distinguishing object of study (morphology versus behaviour) and perspective (ultimate versus proximate). Although traits are known to develop and evolve semi-independently, they are matched together in development and evolution to produce a unique functional phenotype. Here I highlight similarities shared by both traits, such as the decisive role played by the environment for their ontogeny. Considering the widespread developmental and functional entanglement between both traits, many cases of adaptive evolution are better understood when proximate and ultimate explanations are integrated. A field integrating these perspectives is evolutionary developmental biology (evo-devo), which studies the developmental basis of phenotypic diversity. Ultimate aspects in evo-devo studies—which have mostly focused on morphological traits—could become more apparent when behaviour, ‘the integrator of form and function’, is integrated into the same framework of analysis. Integrating a trait such as behaviour at a different level in the biological hierarchy will help to better understand not only how behavioural diversity is produced, but also how levels are connected to produce functional phenotypes and how these evolve. A possible framework to accommodate and compare form and function at different levels of the biological hierarchy is outlined. At the end, some methodological issues are discussed.

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Developmental Mechanisms Linking Form and Function During Jaw Evolution

10.1101/264556 ◽

2018 ◽

Author(s):

Katherine C. Woronowicz ◽

Stephanie E. Gline ◽

Safa T. Herfat ◽

Aaron J. Fields ◽

Richard A. Schneider

Keyword(s):

Mechanical Load ◽

Adductor Muscle ◽

Mechanical Force ◽

Connective Tissues ◽

Tgfβ Signaling ◽

Form And Function ◽

Tendon Insertion ◽

Species Specific ◽

And Function ◽

Development And Evolution

AbstractHow does form arise during development and change during evolution? How does form relate to function, and what enables embryonic structures to presage their later use in adults? To address these questions, we leverage the distinct functional morphology of the jaw in duck, chick, and quail. In connection with their specialized mode of feeding, duck develop a secondary cartilage at the tendon insertion of their jaw adductor muscle on the mandible. An equivalent cartilage is absent in chick and quail. We hypothesize that species-specific jaw architecture and mechanical forces promote secondary cartilage in duck through the differential regulation of FGF and TGFβ signaling. First, we perform transplants between chick and duck embryos and demonstrate that the ability of neural crest mesenchyme (NCM) to direct the species-specific insertion of muscle and the formation of secondary cartilage depends upon the amount and spatial distribution of NCM-derived connective tissues. Second, we quantify motility and build finite element models of the jaw complex in duck and quail, which reveals a link between species-specific jaw architecture and the predicted mechanical force environment. Third, we investigate the extent to which mechanical load mediates FGF and TGFβ signaling in the duck jaw adductor insertion, and discover that both pathways are mechano-responsive and required for secondary cartilage formation. Additionally, we find that FGF and TGFβ signaling can also induce secondary cartilage in the absence of mechanical force or in the adductor insertion of quail embryos. Thus, our results provide novel insights on molecular, cellular, and biomechanical mechanisms that couple musculoskeletal form and function during development and evolution.

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Micro Computed Tomography as an Accessible Imaging Platform for Exploring Organism Development and Human Disease Modeling

10.1101/391300 ◽

2018 ◽

Author(s):

Todd A. Schoborg ◽

Samantha L. Smith ◽

Lauren N. Smith ◽

H. Douglas Morris ◽

Nasser M. Rusan

Keyword(s):

Computed Tomography ◽

Disease Modeling ◽

Imaging Techniques ◽

Model Organisms ◽

Micro Computed Tomography ◽

Animal Development ◽

Form And Function ◽

Size And Morphology ◽

And Function ◽

Rapid Processing

ABSTRACTUnderstanding how events at the molecular and cellular scales contribute to tissue form and function is key to uncovering mechanisms driving animal development, physiology and disease. Elucidating these mechanisms has been enhanced through the study of model organisms and the use of sophisticated genetic, biochemical and imaging tools. Here we present an optimized method for non-invasive imaging of Drosophila melanogaster at high resolution using micro computed tomography (μ-CT). Our method allows for rapid processing of intact animals at any developmental stage, provides precise quantitative assessment of tissue size and morphology, and permits analysis of inter-organ relationships. We then use the power of μ-CT imaging to model human diseases through the characterization of microcephaly in the fly. Our work demonstrates that μ-CT is a versatile and accessible tool that complements standard imaging techniques, capable of uncovering novel biological mechanisms that have remained undocumented due to limitations of current methods.

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Microbiomes In Natura : Importance of Invertebrates in Understanding the Natural Variety of Animal-Microbe Interactions

mSystems ◽

10.1128/msystems.00179-17 ◽

2018 ◽

Vol 3 (2) ◽

Cited By ~ 12

Author(s):

Jillian M. Petersen ◽

Jay Osvatic

Keyword(s):

Human Life ◽

Diverse Range ◽

Functional Roles ◽

Form And Function ◽

Group Interest ◽

Invertebrate Animals ◽

Microbe Interactions ◽

Almost All ◽

And Function ◽

Development And Evolution

ABSTRACT Animals evolved in a world teeming with microbes, which play pivotal roles in their health, development, and evolution. Although the overwhelming majority of living animals are invertebrates, the minority of “microbiome” studies focus on this group. Interest in invertebrate-microbe interactions is 2-fold—a range of immune components are conserved across almost all animal (including human) life, and their functional roles may be conserved. Thus, understanding cross talk between microbes and invertebrate animals can lead to insights of broader relevance. Invertebrates offer unique opportunities to “eavesdrop” on intricate host-microbe conversations because they tend to associate with fewer microbes. On the other hand, considering the vast diversity of form and function that has evolved in the invertebrates, they likely evolved an equally diverse range of ways to interact with beneficial microbes. We have investigated only a few of these interactions in detail; thus, there is still great potential for fundamentally new discoveries.

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FGF and TGFβ signaling link form and function during jaw development and evolution

Developmental Biology ◽

10.1016/j.ydbio.2018.05.002 ◽

2018 ◽

Vol 444 ◽

pp. S219-S236 ◽

Cited By ~ 11

Author(s):

Katherine C. Woronowicz ◽

Stephanie E. Gline ◽

Safa T. Herfat ◽

Aaron J. Fields ◽

Richard A. Schneider

Keyword(s):

Tgfβ Signaling ◽

Form And Function ◽

And Function ◽

Development And Evolution ◽

Jaw Development

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Scanning tunneling microscopy (STM) of DNA and RNA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152148 ◽

1989 ◽

Vol 47 ◽

pp. 34-35

Author(s):

Patricia G. Arscott ◽

Gil Lee ◽

Victor A. Bloomfield ◽

D. Fennell Evans

Keyword(s):

Molecular Structures ◽

Inorganic Materials ◽

Resolving Power ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Form And Function ◽

Dna And Rna ◽

Calf Thymus ◽

And Function ◽

The Relationship

STM is one of the most promising techniques available for visualizing the fine details of biomolecular structure. It has been used to map the surface topography of inorganic materials in atomic dimensions, and thus has the resolving power not only to determine the conformation of small molecules but to distinguish site-specific features within a molecule. That level of detail is of critical importance in understanding the relationship between form and function in biological systems. The size, shape, and accessibility of molecular structures can be determined much more accurately by STM than by electron microscopy since no staining, shadowing or labeling with heavy metals is required, and there is no exposure to damaging radiation by electrons. Crystallography and most other physical techniques do not give information about individual molecules.We have obtained striking images of DNA and RNA, using calf thymus DNA and two synthetic polynucleotides, poly(dG-me5dC)·poly(dG-me5dC) and poly(rA)·poly(rU).

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