We would like to acknowledge our advisor, Dr. Eve Marder. This research was supported by National Institute of Health grants NS17813 to Eve Marder and NS059255 to A-E T.

<ol>
<li>Before dissection the lobster should be buried in ice for 30 minutes to anesthetize the animal.</li>
<li>The sex of the lobster can be determined by looking at the shape of the first swimmeret. Males have boney swimmerets and females have feathery swimmerets. <img src="/files/ftp_upload/1320/1320fig1.png" alt="" /></li>
<li>Isolate the cephalothorax.<ol>
<li>Use a twisting motion to rip off the front claws.</li>
<li>Remove the abdomen (tail portion) by using the large scissors to make a deep cut between the cephalothorax and abdomen. This cuts the giant fiber tracts controlling the tail flip response. Then proceed to cut off the abdomen.</li>
<li>Remove the antennae by trimming them off with scissors, and twist off the legs and the third maxillipeds.</li>
</ol></li>
<li>Remove the carapace from around the stomach, (i.e. the head region between the cervical groove and the rostrum).<ol>
<li>Starting on the lateral edge of this section use rongeurs and spatula to carefully remove the hard carapace, while leaving the reddish underlying hypodermis intact. The spatula is useful for separating the layers so that the carapace can be broken off with the rongeurs.</li>
<li>Moving toward the eyes you find bilateral lightly calcified small oval plates (IIIa ossicles). As close as possible to these ossicles, carefully detach the muscle from the ossicles using the small scissors.</li>
<li>Using spatula and rongeurs remove carapace from between the eyes and the caudal portion (approx. 1 centimeter) of the rostrum.</li>
</ol></li>
<li>Detach the face (region including eyes, and rostrum).<ol>
<li>Using small scissors make a horizontal cut across the most rostral exposed tissue in the rostrum to detach it from the exoskeleton. Then use edge of scissors and/or spatula to carefully roll tissue caudally, just past the level of the IIIa ossicles.</li>
<li>Starting dorsally, use small scissors to detach remaining tissue from the face exoskeleton. Cut as close to the hard carapace as possible, stopping when you get near the center and attachment of the mouth.</li>
<li>From ventral view the mandibles should be easily visible. Detach remaining maxillipeds.</li>
<li>Locate soft lip under the mandibles.</li>
<li>Make lateral cuts to detach the face while keeping the lip attached to the stomach. (There is a slightly curved bluish outer mouth part that can be used as a guide.)</li>
</ol></li>
<li>Detach and remove the stomach.<ol>
<li>Hold the lobster in the palm of your hand, ventral side up and so that the anterior end is toward your elbow.</li>
<li>Attach a hemostat to the lip and let gravity pull the hemostat and lip down and away from the ventral body wall.</li>
<li>Using small scissors cut out mandibles.</li>
<li>Locate the dorsal side of the ventral body wall, which forms a hard &ldquo;shelf&rdquo; ventral to lip and stomach. Cut just below the "shelf", very close to the body wall, across the entire medial-lateral midline. The entire ventral side of the stomach should now be detached from the body wall.</li>
<li>Turn the lobster so that the dorsal side is up. Cut along the rostral edge of the cervical groove, where the carapace was removed, and gently pulls the stomach out.</li>
<li>Detach any extra intestines that remain attached to the stomach.</li>
</ol></li>
<li>Open the stomach, and prepare it for pinning.<ol>
<li>Hold the stomach in the palm of your hand with the hypodermis-side down. The hemostat should still be attached to the lip and should lie between your fingers.</li>
<li>Use small scissors to make a shallow anterior-to-posterior cut from the mouth opening (below the lip) down through the ventral side of the pylorus.</li>
<li>To further open the stomach, make two lateral cuts along the ossicles running across the center of the stomach.</li>
<li>Cold saline may be poured into the stomach to improve visibility and expel stomach contents.</li>
<li>In order to allow the preparation to lay flat in the dissecting dish use the small scissors to trim the three gastric teeth.</li>
</ol></li>
<li>Pin the stomach down in the dissection dish.<ol>
<li>Place the stomach, hypodermis-side up, in a saline-filled dissection dish.</li>
<li>Place insect pins at the lip and the four corners created when the stomach was opened up. For the anterior corners place pins high and close to the edge, as not to disturb commissural ganglia or inferior oesophageal nerves. For the posterior corners place pins slightly high as not to disturb the pyloric dilator muscle.</li>
</ol></li>
</ol>

<ol>
	<li>Marder, E., Bucher, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Central+pattern+generators+and+the+control+of+rhythmic+movements.">Central pattern generators and the control of rhythmic movements.</a> Curr. Biol. 11, R986-R996 (2001).</li><li>Nusbaum, M. P., Beenhakker, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+small-systems+approach+to+motor+pattern+generation.">A small-systems approach to motor pattern generation.</a> Nature. 417, 343-350 (2002).</li><li>Clemens, S., Massabuau, J. C., Legeay, A., Meyrand, P., Simmers, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+modulation+of+interacting+central+pattern+generators+in+lobster+stomatogastric+ganglion:+influence+of+feeding+and+partial+pressure+of+oxygen.">In vivo modulation of interacting central pattern generators in lobster stomatogastric ganglion: influence of feeding and partial pressure of oxygen.</a> J. Neurosci. 18, 2788-2799 (1998).</li><li>Tobin, A. E., Bierman, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Homarus+americanus+stomatogastric+nervous+system+dissection.">Homarus americanus stomatogastric nervous system dissection.</a> J Vis Exp. 27, (2009).</li><li>Maynard, D. M., Dando, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+structure+of+the+stomatogastric+neuromuscular+system+in+Callinectes+sapidus,+Homarus+Americanus+and+Panulirus+argus+(Decapoda+crustacean).">The structure of the stomatogastric neuromuscular system in Callinectes sapidus, Homarus Americanus and Panulirus argus (Decapoda crustacean).</a> Philos. Trans. R. Soc. Lond. B Biol. Sci. 268, 161-220 (1974).</li><li>Herrick, F. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+history+of+the+American+Lobster.">Natural history of the American Lobster.</a> U.S. Bur. Fish. , 219-252 (1909).</li><li>Marder, E., Bucher, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding+circuit+dynamics+using+the+stomatogastric+nervous+system+of+lobsters+and+crabs.">Understanding circuit dynamics using the stomatogastric nervous system of lobsters and crabs.</a> Annu. Rev. Physiol. 69, 291-316 (2007).</li></ol>

In our laboratory dissection of the lobster stomach is done to access the stomatogastric nervous system, a network that controls the rhythmic contractions of the stomach. The anatomy of lobster stomach has been well described previously5-7, and we recommend becoming familiar with its anatomy. Doing so will reduce the risk of damaging the delicate nerves and muscle.
Upon completion of the stomach dissection, various portions of the STNS may be further dissected. For example to st...

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Homarus americanus</td>
<td>&nbsp;</td>
<td>Commercial Lobster</td>
<td>&nbsp;</td>
<td>Can be purchased from any lobster supplier, We specifically request &#x201C;chicken&#x201D; lobsters.</td>
</tr>
<tr>
<td>Black Sylgard 170</td>
<td>&nbsp;</td>
<td>Dow Corning</td>
<td>170</td>
<td>&nbsp;</td>
<tr>
<td>Preparation Dish</td>
<td>&nbsp;</td>
<td>Fischer </td>
<td>08-807</td>
<td>Fill 2" with Black Sylgard 170.</td>
</tr>
<tr>
<td>Fine Scissors</td>
<td>&nbsp;</td>
<td>FST</td>
<td>14090-09</td>
<td>&nbsp;</td>
<tr>
<td>Insect Pins size 6</td>
<td>&nbsp;</td>
<td>FST</td>
<td>26000-65</td>
<td>&nbsp;</td>
<tr>
<td>Mayo Scissors</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>This is a common product offered by many suppliers of dissecting tools.</td>
</tr>
<tr>
<td>Micro-Spatula</td>
<td>&nbsp;</td>
<td>Ward Sci.</td>
<td>15 V 4313</td>
<td>This is a very common product offered by many suppliers of lab tools.</td>
</tr>
<tr>
<td>Rongeurs</td>
<td>&nbsp;</td>
<td>FST</td>
<td>&nbsp;</td>
<td>16000-14</td>
</tr>
<tr>
<td>Plastic hemostat</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>This is a common product offered by many suppliers of dissecting or jewelry making tools.</td>
</tr>		</tbody>
		</table>
		</div>

gross dissection of the stomach of the lobster, homarus americanus

The stomach of the American lobster (Homarus americanus) is located in the cephalothorax, between the rostrum and the cervical groove. The anterior end of the stomach is defined by the mouth opening and the posterior end by the bottom of the pylorus. Along the dorsal side of the stomach lies the stomatogastric nervous system (STNS). This nervous system, which contains rhythmic networks that underlie feeding behavior, is an established model system for studying rhythm generating networks and neuromodulation 1,2. While it is possible to study this system in vivo 3, the STNS continues to produce its rhythmic activity when isolated in vitro. In order to study this system in vitro the stomach must be removed from the animal. This video article describes how the stomach can be dissected from the American lobster. In an accompanying video article4 we demonstrate how the STNS can be isolated from the stomach.

Watch this Scientific Journal Video about Gross Dissection of the Stomach of the Lobster, Homarus Americanus at JoVE.com

Gross Dissection of the Stomach of the Lobster, Homarus Americanus

We describe the gross dissection of the stomach of the American lobster (Homarus americanus).

Gross Dissection of the Stomach of the Lobster, Homarus Americanus

The stomach of the American lobster (Homarus americanus) is located in the cephalothorax, between the rostrum and the cervical groove. The anterior end of ...

gross-dissection-of-the-stomach-of-the-lobster-homarus-americanus

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14.5K Views.  Brandeis. We describe the gross dissection of the stomach of the American lobster (Homarus americanus).

Video: Gross Dissection of the Stomach of the Lobster, Homarus Americanus

Dissection of Drosophila Ovaries

Micro-dissection of Rat Brain for RNA or Protein Extraction from Specific Brain Region

Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates micro-dissection of four major brain regions include olfactory bulb, frontal cortex, striatum and hippocampus in fresh rat brain tissue. Useful tips for quick removal of respective regions to avoid RNA and protein degradation of the tissue are given.

Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates micro-dissection of four major brain regions include olfactory bulb, frontal cortex, striatum and hippocampus in fresh rat brain tissue. Useful tips for quick removal of respective regions to avoid RNA and protein degradation of the tissue are given.

Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates ...

Homarus Americanus Stomatogastric Nervous System Dissection

With the goal of understanding how nervous systems produce activity and respond to the environment, neuroscientists turn to model systems that exhibit the activity of interest and are accessible and amenable to experimental methods. The stomatogastric nervous system (STNS) of the American lobster (Homarus americanus; also know was the Atlantic or Maine lobster) has been established as a model system for studying rhythm generating networks and neuromodulation of networks. The STNS consists of 3 anterior ganglia (2 commissural ganglia and an oesophageal ganglion), containing modulatory neurons that project centrally to the stomatogastric ganglion (STG). The STG contains approximately 30 neurons that comprise two central pattern generating networks, the pyloric and gastric networks that underlie feeding behaviors in crustaceans1,2. While it is possible to study this system in vivo3, the STNS continues to produce its rhythmic activity when isolated in vitro. Physical isolation of the STNS in a dish allows for easy access to the somata in the ganglia for intracellular electrophysiological recordings and to the nerves of the STNS for extracellular recordings. Isolating the STNS is a two-part process. The first part, dissecting the stomach from the animal, is described in an accompanying video article4. In this video article, fine dissection techniques are used to isolate the STNS from the stomach. This procedure results in a nervous system preparation that is available for electrophysiological recordings.

Homarus Americanus Stomatogastric Nervous System Dissection

We describe the fine dissection of the stomatogastric nervous system from the stomach of the American lobster (Homarus americanus).

With the goal of understanding how nervous systems produce activity and respond to the environment, neuroscientists turn to model systems that exhibit the ...

Gross and Fine Dissection of Inner Ear Sensory Epithelia in Adult Zebrafish (Danio rerio)

Neurosensory epithelia in the inner ear are the crucial structures for hearing and balance functions. Therefore, it is important to understand the cellular and molecular features of the epithelia, which are mainly composed of two types of cells: hair cells (HCs) and supporting cells (SCs). Here we choose to study the inner ear sensory epithelia in adult zebrafish not only because the epithelial structures are highly conserved in all vertebrates studied, but also because the adult zebrafish is able to regenerate HCs, an ability that mammals lose shortly after birth. We use the inner ear of adult zebrafish as a model system to study the mechanisms of inner ear HC regeneration in adult vertebrates that could be helpful for clinical therapy of hearing/balance deficits in human as a result of HC loss.
Here we demonstrate how to do gross and fine dissections of inner ear sensory epithelia in adult zebrafish. The gross dissection removes the tissues surrounding the inner ear and is helpful for preparing tissue sections, which allows us to examine the detailed structure of the sensory epithelia. The fine dissection cleans up the non-sensory-epithelial tissues of each individual epithelium and enables us to examine the heterogeneity of the whole epithelium easily in whole-mount epithelial samples.

Gross and Fine Dissection of Inner Ear Sensory Epithelia in Adult Zebrafish Danio rerio

The inner ear sensory epithelium of adult zebrafish is a good model system for understanding the mechanisms of hair cell regeneration in adult vertebrates. This protocol demonstrates the fine dissection of the epithelia, through which we can get tissue samples for studying the regenerative events at cellular and subcellular levels.

Neurosensory epithelia in the inner ear are the crucial structures for hearing and balance functions. Therefore, it is important to understand the ...

Dissection of Organs from the Adult Zebrafish

Over the last 20 years, the zebrafish has become a powerful model organism for understanding vertebrate development and disease.  Although experimental analysis of the embryo and larva is extensive and the morphology has been well documented, descriptions of adult zebrafish anatomy and studies of development of the adult structures and organs, together with techniques for working with adults are lacking. The organs of the larva undergo significant changes in their overall structure, morphology, and anatomical location during the larval to adult transition.  Externally, the transparent larva develops its characteristic adult striped pigment pattern and paired pelvic fins, while internally, the organs undergo massive growth and remodeling.  In addition, the bipotential gonad primordium develops into either testis or ovary.  This protocol identifies many of the organs of the adult and demonstrates methods for dissection of the brain, gonads, gastrointestinal system, heart, and kidney of the adult zebrafish. The dissected organs can be used for in situ hybridization, immunohistochemistry, histology, RNA extraction, protein analysis, and other molecular techniques.  This protocol will assist in the broadening of studies in the zebrafish to include the remodeling of larval organs, the morphogenesis of organs specific to the adult and other investigations of the adult organ systems.

This protocol describes a procedure for identifying and dissecting organs from the adult zebrafish.

Over the last 20 years, the zebrafish has become a powerful model organism for understanding vertebrate development and disease.  Although experimental ...

Using SCOPE to Identify Potential Regulatory Motifs in Coregulated Genes

SCOPE is an ensemble motif finder that uses three component algorithms in parallel to identify potential regulatory motifs by over-representation and motif position preference1. Each component algorithm is optimized to find a different kind of motif. By taking the best of these three approaches, SCOPE performs better than any single algorithm, even in the presence of noisy data1. In this article, we utilize a web version of SCOPE2 to examine genes that are involved in telomere maintenance. SCOPE has been incorporated into at least two other motif finding programs3,4 and has been used in other studies5-8. 
The three algorithms that comprise SCOPE are BEAM9, which finds non-degenerate motifs (ACCGGT), PRISM10, which finds degenerate motifs (ASCGWT), and SPACER11, which finds longer bipartite motifs (ACCnnnnnnnnGGT). These three algorithms have been optimized to find their corresponding type of motif. Together, they allow SCOPE to perform extremely well.
Once a gene set has been analyzed and candidate motifs identified, SCOPE can look for other genes that contain the motif which, when added to the original set, will improve the motif score. This can occur through over-representation or motif position preference. Working with partial gene sets that have biologically verified transcription factor binding sites, SCOPE was able to identify most of the rest of the genes also regulated by the given transcription factor.
Output from SCOPE shows candidate motifs, their significance, and other information both as a table and as a graphical motif map. FAQs and video tutorials are available at the SCOPE web site which also includes a "Sample Search" button that allows the user to perform a trial run. 
Scope has a very friendly user interface that enables novice users to access the algorithm's full power without having to become an expert in the bioinformatics of motif finding. As input, SCOPE can take a list of genes, or FASTA sequences. These can be entered in browser text fields, or read from a file. The output from SCOPE contains a list of all identified motifs with their scores, number of occurrences, fraction of genes containing the motif, and the algorithm used to identify the motif. For each motif, result details include a consensus representation of the motif, a sequence logo, a position weight matrix, and a list of instances for every motif occurrence (with exact positions and "strand" indicated). Results are returned in a browser window and also optionally by email. Previous papers describe the SCOPE algorithms in detail1,2,9-11.

A straight-forward and robust method to identify potential regulatory motifs in co-regulated genes is presented. SCOPE does not require any user parameters and returns motifs that represent excellent candidates for regulatory signals. The identification of such regulatory signals helps to understand the underlying biology.

SCOPE is an ensemble motif finder that uses three component algorithms in parallel to identify potential regulatory motifs by over-representation and ...

Dissection of the Adult Zebrafish Kidney

Researchers working in the burgeoning field of adult stem cell biology seek to understand the signals that regulate the behavior and function of stem cells during normal homeostasis and disease states. The understanding of adult stem cells has broad reaching implications for the future of regenerative medicine1. For example, better knowledge about adult stem cell biology can facilitate the design of therapeutic strategies in which organs are triggered to heal themselves or even the creation of methods for growing organs in vitro that can be transplanted into humans1. The zebrafish has become a powerful animal model for the study of vertebrate cell biology2. There has been extensive documentation and analysis of embryonic development in the zebrafish3. Only recently have scientists sought to document adult anatomy and surgical dissection techniques4, as there has been a progressive movement within the zebrafish community to broaden the applications of this research organism to adult studies. For example, there are expanding interests in using zebrafish to investigate the biology of adult stem cell populations and make sophisticated adult models of diseases such as cancer5. Historically, isolation of the zebrafish adult kidney has been instrumental for studying hematopoiesis, as the kidney is the anatomical location of blood cell production in fish6,7. The kidney is composed of nephron functional units found in arborized arrangements, surrounded by hematopoietic tissue that is dispersed throughout the intervening spaces. The hematopoietic component consists of hematopoietic stem cells (HSCs) and their progeny that inhabit the kidney until they terminally differentiate8. In addition, it is now appreciated that a group of renal stem/progenitor cells (RPCs) also inhabit the zebrafish kidney organ and enable both kidney regeneration and growth, as observed in other fish species9-11. In light of this new discovery, the zebrafish kidney is one organ that houses the location of two exciting opportunities for adult stem cell biology studies. It is clear that many outstanding questions could be well served with this experimental system. To encourage expansion of this field, it is beneficial to document detailed methods of visualizing and then isolating the adult zebrafish kidney organ. This protocol details our procedure for dissection of the adult kidney from both unfixed and fixed animals.
Dissection of the kidney organ can be used to isolate and characterize hematopoietic and renal stem cells and their offspring using established techniques such as histology, fluorescence activated cell sorting (FACS)11,12, expression profiling13,14, and transplantation11,15. 
We hope that dissemination of this protocol will provide researchers with the knowledge to implement broader use of zebrafish studies that ultimately can be translated for human application.

The zebrafish kidney is home to both renal and hematopoietic adult stem/progenitor cells, and represents an outstanding opportunity to study these cell types and their progeny in a vertebrate model organism. Here, we demonstrate a detailed dissection procedure that enables the researcher to identify and surgically remove the adult zebrafish kidney, which can be used for applications such as cell isolation, transplantation, and expression studies of kidney and/or blood cell populations.

Researchers working in the burgeoning field of adult stem cell biology seek to understand the signals that regulate the behavior and function of stem ...

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The branchial skeleton, including gill rakers, pharyngeal teeth, and branchial bones, serves as the primary site of food processing in most fish. Here we describe a protocol to dissect and flat-mount this internal skeleton in threespine sticklebacks. This method is also applicable to a variety of other fish species.

The posterior pharyngeal segments of the vertebrate head give rise to the branchial skeleton, the primary site of food processing in fish. The morphology ...

Dissection of the Auditory Bulla in Postnatal Mice: Isolation of the Middle Ear Bones and Histological Analysis

In most mammals, auditory ossicles in the middle ear, including the malleus, incus and stapes, are the smallest bones. In mice, a bony structure called the auditory bulla houses the ossicles, whereas the auditory capsule encloses the inner ear, namely the cochlea and semicircular canals. Murine ossicles are essential for hearing and thus of great interest to researchers in the field of otolaryngology, but their metabolism, development, and evolution are highly relevant to other fields. Altered bone metabolism can affect hearing function in adult mice, and various gene-deficient mice show changes in morphogenesis of auditory ossicles in utero. Although murine auditory ossicles are tiny, their manipulation is feasible if one understands their anatomical orientation and 3D structure. Here, we describe how to dissect the auditory bulla and capsule of postnatal mice and then isolate individual ossicles by removing part of the bulla. We also discuss how to embed the bulla and capsule in different orientations to generate paraffin or frozen sections suitable for preparation of longitudinal, horizontal, or frontal sections of the malleus. Finally, we enumerate anatomical differences between mouse and human auditory ossicles. These methods would be useful in analyzing pathological, developmental and evolutionary aspects of auditory ossicles and the middle ear in mice.

We present a protocol to isolate the auditory bulla, capsule, and ossicles from postnatal mice for whole mount and histological analysis.

In most mammals, auditory ossicles in the middle ear, including the malleus, incus and stapes, are the smallest bones. In mice, a bony structure called ...

Reverse Dissection and DiceCT Reveal Otherwise Hidden Data in the Evolution of the Primate Face

Facial expressions, or facial displays, of social or emotional intent are produced by many mammalian taxa as a means of visually communicating with conspecifics at a close range. These displays are achieved by contraction of the mimetic muscles, which are skeletal muscle attached to the dermis of the face. Reverse dissection, removing the full facial mask from the skull and approaching mimetic muscles in reverse, is an effective but destructive way of revealing the morphology of mimetic muscles but it is destructive. DiceCT is a novel mechanism for visualizing skeletal muscles, including mimetic muscles, and isolating individual muscle fascicles for quantitative measurement. Additionally, DiceCT provides a non-destructive mechanism for visualizing muscles. The combined techniques of reverse dissection and DiceCT can be used to assess the evolutionary morphology of mimetic musculature as well as potential contraction strength and velocity in these muscles. This study further demonstrates that DiceCT can be used to accurately and reliably visualize mimetic muscles as well as reverse dissection and provide a non-destructive method for sampling mimetic muscles.

Facial expressions are a mode of visual communication produced by mimetic muscles. Here, we present protocols for the novel techniques of reverse dissection and DiceCT to fully visualize and assess mimetic muscles. These combined techniques can examine both morphological and physiological aspects of mimetic musculature to determine functional aspects.

Facial expressions, or facial displays, of social or emotional intent are produced by many mammalian taxa as a means of visually communicating with ...

Gross Dissection of the Stomach of the Lobster, Homarus Americanus

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Reverse Dissection and DiceCT Reveal Otherwise Hidden Data in the Evolution of the Primate Face