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I want to do research on some insects organs association of functional morphology, there I want steps and procedure to make research. Please help me. Here I have attached pictures for reference
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Dear Babu Kes
The software product will suit you Aidos-X. It is written for entomologists. Many articles are devoted to ground beetles. If you have any questions write.
Regards, Sergey
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The mitochondria present in heart, liver, kidney and brain cells, are they all the same?
Do they have any difference in function, morphology?
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Hi Hari,
Provided that different tissues have different energetic demands, and mitochondria are responsible for producing energy, their morphology and function can readily differ between cell types. However, they can even differ within a single cell, for instance between intermyofibrillar and subsarcolemmal mitochondria in myocytes. Our recent review may be of use to you:
Best,
Kyle
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I'm aware of quite a few sites out there (e.g. morphobrowser, morphosource, nespos, evans) but I'm always looking for more.
In particular, I'm looking for ones that have CT scans high quality enough to do research with...i.e. the Digital Morphology Museum, KUPRI has a TON of amazing primate CT scans for free download. However, they're not particularly high quality, making it difficult to use for anything other than gross geometric measurements and/or teaching.
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Dear colleagues,
For our current project into the functional morphology and evolution of leaping in small new world monkeys, we are looking for postcranial material of the tamarins and marmosets (Primates: Callitrichidae). Specifically, we are looking for museum collections that house lots of (preferentially) disarticulated limb long bones that we could either borrow or CT scan at the location of the collection, if facilities allow. Which collections are worth visiting?
We are also very much interested in getting access to cadavers (fresh and frozen – not formalin fixated), to analyze muscle architectural properties.
We appreciate your help.
Kind regards from Berlin,
John Nyakatura (also on behalf of Patricia Berles and Léo Botton-Divet)
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It’s been a few years, but I seem to remember seeing a lot of marmoset and tamarin postcrania at the Smithsonian in Washington, DC. Their online database is searchable and really easy to use too.
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VMT may be associated with functional and/or morphological effects on the retina. However it may be associated with no functional and/or morphological changes in the retina. However, I have observed intervention even in non symptomatic cases by some of our good Vitreoretinal surgeons.
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I agree with Imtiyaz. Asymptomatic cases need not be surgically corrected. Additionally other co-morbid conditions also have a role to play in decision making.
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In the backdrop of Functional Morphology, what possible advantages these Bees must be having to build a Hive of equable spiral configuration.
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Bees are one of the smart creatures. The planar hexagonal design of honeycomb is purely mathematical. It is to maximize the planar area and boundary in which hexagons have and sake of stability. The helixial design what we see from the graph indicates again the intricate and mathematical design of optimization and stability to create a rising structure to make their honey than on a wide stretch of flat surface which might not hold the weight of the honey and crumbled and fail. This design of bees parallels our urge to build high rise buildings for maximum use of people with small plot of land. We learn more precision and purposeful designs from nature.
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I am trying to find out whether some morphometric data of land planarians (for now, especially position of the dorsal insertion of the pharynx and position of the mouth) can predict their diet, but I am not quite sure about how I could compare the morphometry with the diet.
For now I have two measurements:
1. Relative position of the dorsal insertion of the pharynx in the pharyngeal pouch (which determines the shape of the pharynx);
2. Relative position of the mouth on the pharyngeal pouch.
I also have data on what organisms (prey species) are consumed by some of the species from which I took measurments. I separated the prey into 7 groups: woodlice, harvestmen, earthworms, snails, veronicellid slugs, agriolimacid slugs and other land planarians.
Does anyone have suggestions on how to deal with these data? Thanks in advance!
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Thank you! I'll take a look at the papers.
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I'm searching papers about functional morphology of mammals skull.
Can anyone help me? Thanks Armando
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So many good ones out there!! Eg,
Really too many to list. Start off by looking at papers by S Wroe, P O'Higgins, D Strait...
Is there a specific animal group you are interested in?
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Can anyone give a short explanation about the functional role of cheilocystidia? In several genera of the higher fungi, they have thick walls, or/and encrusted apex. Anyway, what is the function of this formations?
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First, things do not necessary have a function in Nature. Structures that do not impact the fitness of a genotype (neutral traits) will not be eliminated by natural selection and may thus get fixed and transmitted. 
This being said, the function of cystidia, whether cheilo or pleuro, is still unclear. They may play a role in maintaining a higher degree humidity around the gills (boundary layer effect). They may also play a defensive role in protecting  against gills feeding animals. See for instance:
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The presence of Permanent successor may be interfering for testing
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Most of the diagnostic tests, such as vitality tests used in conventional endodontic therapy are of very little, limited or no value in primary teeth and permanent immature teeth.
The pediatric patients generally have a very low pain threshold compared to adults, so they cannot always describe subjective symptoms or sensitivity to a stimulus. Since majority of children perceive the vitality testing methods as unpleasant stimuli, chances of false-positive or falsenegative results are common in children. In primary teeth, due to the lack of development of the plexus of Raschkow in the pulp-dentin complex, pulp tests like thermal and electric tests are unreliable. So, they are used as an adjuvant to the other clinical diagnostic aids in dentistry.
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Curious on the functional role of shell carina in freshwater gastropods
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Dear Ranjeev,
That's a difficult question and there is no simple answer to it. Shell sculpture (as well as shape) can be both ecophenotypic and genetically fixed, depending on the environmental conditions and the presence or absence of competition and predation pressure.
For instance, in the Gyraulus species flock in Miocene Lake Steinheim the evolution of shape and sculpture is considered to reflect partly speciation and partly ecophenotypic variation (see Rasser 2013; attached).
In recent Melanopsis species of the Mediterranean, sculpture and shape are highly variable within single species, which makes species identification based on the shell alone sometimes almost impossible. Apparently, most of the morphological variability seems to be ecophenotypic (e.g. Glaubrecht 1993; Heller & Sivan 2002; attached). 
For another example, I suggest you also see Glaubrecht & Köhler (2004 and references therein; attached).
In summary, shell carination CAN indeed be a result of ecophenotypic plasticity but the difficult task is to prove it!
Best wishes,
thomas
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Lateral, anterior and posterior Fontanelles, which  are gapes in the skull of catfishes, covered by tough membrane, what are the functions of these gaps? 
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Dear Eman,
About what catfishes are you talking? Some catfishes has two cranial fontanelles, others have only one, others have none.
Regards,
Gloria Arratia
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   I am currently studing functional morphology about Ponera (Hymenoptera:Formicidae). What would you suggest is a key issue about the sub-petioler fenestra, that function may be relative hunting, glands or feeding larva etc...? Anyone could give me ideas for your observation or experience? 
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Chi-Man Leong, I am quite sure that taxa within Ectatomminae, Proceratiinae, and Dorylinae also have a subpetiolar process with a fenestra. Check Ectatomma tuberculatum, Typhlomyrmex pusillus, Proceratium and Probolomyrmex speciesAcanthostichus serratulus, Cerapachys nitidulus, Cylindromyrmex brevitarsus, Eciton species, for examples. Regarding the metacoxae, my point was: when an ant curve the gaster downwards to sting something, the subpetiolar process seems to fit somewhere around the metacoxae. Take Tetraponera aethiops as an example, its subpetiolar process has an anterior and a posterior spiniform projection; if the gaster is pointing downwards, the posterior projection would likely hook in between the posterior faces of the metacoxae, while the anterior projection would be in between the metacoxae anterior faces.
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In his 1993 Implied Weights paper (Cladistics 9:83, doi:10.1111/j.1096-0031.1993.tb00209.x), Goloboff states that "Farris et al (at the VIII Meeting of the Society, 1989) show that characters with fewer incompatibilities may nonetheless be more homoplastic".  Would anyone know whether this observation has been published, and where I might find it?
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You get that problem all the time with morphological data: Loose definitions of character states result in a wide range of morphologies considered as similar which would be regarded as incompatible if more strict criteria for similarity had been applied. As a consequence the measured amount of homoplasy (in a cladistic analysis) is higher in case of loose definitions and few incompatibilities than for strict definitions and many incompatibilites. But that appears to be rather trivial ...
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Could anybody suggests any papers where authors describe an algorithm for construction Rapana species 3D models? Or other similar Gastropoda species?
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There are a number of free tools you can use to make a 3D model from photographs. VisualSFM together with Meshlab works nicely.
There are some good tutorials on youtube, this one is perhaps the best:
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With two colleagues, I have just finished taxonomic revision of the genera hitherto included in the subfamily Discotettiginae (Orthoptera: Caelifera: Tetrigidae), id est genera Discotettix, Phaesticus, Arulenus, Kraengia, Rosacris, Flatocerus, Hirrius and a new genus. We found out that Discotettiginae is paraphyletic taxon composed of genera that share unique antennal morphology - basal segments (I-VI) usually filiform, while subapical/anteapical (VII-IX/X) are foliaceous - flattened. The same antennal morphology can be observed in Hemipteran geus Dalader. Furthermore, the coloration of antennae in Dalader is the same as one found in e.g. Phaesticus and Rosacris. Since both taxa occur in SE Asia, I am interested if anybody has any idea about purpose/function of such morphology. I would be very grateful if somebody can provide also more examples of this and suggest if their function could be mimicry (to what?) or something else. Thank you in advance.
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hello, taking this up again and probably opening a new thread: have a look at this picture of Aphonomorphus (Aphonomorphus) duplovenatus http://orthoptera.speciesfile.org/common/basic/ShowImage.aspx?TaxonNameID=1124957&ImageID=151854
it looks as if it has clubshaped cerci! Type,and it seems male is unknown.
Any ideas?Greetings Klaus Riede
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There seems to be no well-published detailed research on the haired snails except Pfenninger et al., 2005 ("Why do snails have hairs?..."), but this work is not morphological... I know also an older work on Trochulus hispidus (Trichia hispida) - Kaiser, 1966.
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Dear Balashov,
hope this of  use
A hairy business-periostracal hair formation in two species of helicoid snails (gastropoda, stylommatophora, helicoidea). 
Best regards
Deepak
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Many extant birds use mechanical sounds, or sonations, intentionally as communicative signals; most often in the context of courtship, and usually made by the wings or other feathers.  
Behaviour does not fossilize particularly well, so we are pretty clueless about what the courtship displays of avian ancestors and primitive birds may have sounded like, or been produced by. But for fun, does anyone think that wings (and other feathers) could have been used to produce acoustic signals during courtship?  What might they have sounded like? What might this tell us about the use of sonations, and evolution of vocalization and vocal learning among other reptiles and birds respectively? 
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Hi Justin and Syed,
This can, of course, only be purely speculative. We can predict something about dinosaur hearing (Gleich, O., Dooling, R.J., Manley, G.A. (2005) Audiogram, body mass, and basilar papilla length: correlations in birds and predictions for extinct archosaurs. Natur-wissenschaften 92, 595-598.  and Walsh, S.A., Barrett, P.M., Milner, A.C., Manley, G.A., Witmer, L.M. (2009) Inner ear anatomy is a proxy for deducing auditory capability and behaviour in reptiles and birds. Proc. Roy. Soc. B. 276, 1355-1360.), but putting reliable limits on frequency ranges and, especially, sensitivity, is not possible. We recently showed that although it is known that male Caparcaillie produce very-low-frequency sounds with their wings (Lieser, M., Berthold, P., Manley, G.A. (2005) Infrasound in the capercaillie (Tetrao urogallus).. J. Ornithol. 146, 395-398), the females do not respond to such sounds (Lieser, M., Berthold, P., Manley, G.A. (2006) Infrasound in the flutter jumps of the capercaillie (Tetrao urogallus): apparently a physical by-product. J. Ornithol. 147, 507-509.). The frequencies produced by such fluttering wings would, of course, by of higher frequency if the feathered dinosaurs were smaller than Capercaillie.
Detection is a product of hearing sensitivity and distance, making it even harder to speculate whether feathered dinosaurs used such sounds to communicate, as we have no idea how sensitive or how loud they were. If we knew more about their environment, we might understand better the selection pressures on communication. For example: Did they live in dense vegetation and be - generally - unable to see each other?
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Let's say, I have landmark data for three different structures (A,B,C; e.g. three different teeth along the tooth row or fingers on one hand) for one sample of specimens and I would like to know whether structure A is stronger integrated with structure B than structure B with structure C. Is it possible to compare RV-coefficients calculated for the A-B and B-C interaction and would the resulting difference be valid to make inferences on relative integration strengths?
I have already asked some colleagues about the problem but got somewhat contradicting answers. So I am curious about your opinons. Maybe comparing the values would be possible under the condition of the same landmark number on all structures?!
Best regards,
Stefan
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Well, a problem is that the RV coefficient makes little sense for biological structures because it ignores spatial scale and the distribution of landmarks across a structure. 
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I am doing a research project that compares the insulative properties of different feather coats (using specimens). However, in order to do this, I need a small heat plate (i.e. less than 7x7 cm) in which I can control the temperature very precisely. I cannot seem to find anything that suits my needs doing a quick search and I was wondering if anyone had any ideas, or if anyone has used any products that fit this description. Thanks in advance!
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It would be easy on live birds, but on museum bird skins harder.  Shouldn't make any difference what termp is behind the skin.  I think I would measure some live birds to make sure the measurements on the dead skins make sense.  I work with elephants and other big beasts, live no skins.
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I know that in years past, it has often been suggested that predatory maniraptoran dinosaurs (mainly troodontids and dromaeosaurids) used their forelimbs to catch food. Indeed, Ostrom originally suggested that flapping behavior began as an extrapolation of the prey catching stroke. However, now that we know more about the anatomy of these predatory dinosaurs, specifically that many forms had large secondary and primary feathers on their arms and were incapable of pronating their hands, I am having a hard time seeing how the forelimbs could have been of any use in predatory behavior. There doesn't seem to be any way that they could have been rotated to grab prey, nor slash at conspecifics or larger prey items. Yet there has to have been some function for having flexible clawed digits in maniraptorans, as nearly all maniraptorans have well-developed hands, and indeed many early birds still had well-developed digits.
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I remember a poster at the SVP meeting in Berlin this year (2014) about the grasping capabilities of a non-maniraptoran coelurosaur:
SULLIVAN, Yu, Xu 2014, MANUAL FLEXIBILITY AND GRASPING ABILITY IN THE BASAL TYRANNOSAUROID DINOSAUR GUANLONG WUCAII. Journal of Vertebrate Paleontology, Program and Abstracts, 2014, page 237
Perhaps thinking about the hands of the sistergroup to Maniraptora within the Coelurosauria offers some interesting ideas.
edit: removed a typo
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Hi! I have a 3D-GMM data set of carnivore skulls and I would like to calculate the Procrustes distance of every individual specimen to a predefined shape after the Procrustes superimposition. In which (open source) software can I do that relatively straightforward and how? Thanks in advance!
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Hi Stefan,
Even that you got answers that helped you to solve the problem, here I provided a R code that can help you to do the same stuff in R statistical environment. R is in a pure sense an open source (not only freeware software). 
As Sascha said, doing this in R you will be able to enjoy a power of R's flexibility and advanced analyses. Even more, it provides an intuitive way how Procrustes distance is actually calculated (and programmed).
Code is in the attachment.
Hope this will help.
Marko
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I am looking for data on bite forces of extant Artidactyla and Perissodactyla. Anything is welcome, like experimental data or FEM calculations.
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While there may not be exactly the data you are looking for, the Feeding Experiments End-User Database (FEED) may have some information that would provide the basis for a first approximation "one-off" calculation.
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While forming spherical Ag NPs they converted into fibre like structure. I was reducing AgNo3 with NaBH4 using tri sodium as capping agent.
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Thank you Emily,
By the way I added 1.3 mg of tri sodium citrate in 50 ml of AgNo3 solution ( 0.1 mM so that is 0.88 mg) and 10 ml of NaBH4 ( 2mM so .76 mg) . Do you think I should increase the amount of capping agent?
and after adding tri sodium citrate , I did the ligand exchange reaction with 3-chloro 1-propane thiol which replaced the capping agent and after that i did azide functionalization with NaN3. Which capping agent you have used for preparation of AgNPs?
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So, as many of you are probably aware, there are several living groups of fish which are able to use electroreception to some degree to either passively sense the world around them or, in some cases, actually stun or kill other animals. In particular, I'm thinking of members of the Gymnotiformes (including the electric eel), the electric catfish (Malapteruridae), the torpedo rays (Torpediniformes) and several families of the Osteoglossiformes (Mormyridae and Gymnarchidae).
I was wondering if anyone knew of any evidence that a now totally-extinct group of fish may have possessed similar electroreceptive/generative abilities (that is to actually generate electric fields, rather than sense them as in sharks or paddlefish). I know that in South American knifefish (Gymnotiformes), the development of an electricity-generating system has strongly constrained the development of their locomotion, which makes me wonder whether a similar morphology among extinct fish (say, xenacanth sharks) might be indicative of such behavior.
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I vaguely remember that I heard some theories about Galeaspida or Osteostraci possibly having an electrogenetic sense.
But the only "reference" I can give you at the moment is just the page about Osteostraci on the tree of life project page:
I (or you) will have to dive more deeply into the literature aboput them to get some usefull, quoteable references.
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How the environment the prey has been caught in, and prey itself can affect snake’s cranial morphology? Which bones and their features (length, width, height) affect snakes adaptation (fitness)? I'm particularly interested in data on the core Macrostomata group (pythons and boas).
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Thank you Gordon W Schuett for your answer. I will check David Cundall work. Im already reading about intramaxillary joint in O. Reippel works but I will also check Cundall & Irish (1989) work.
Im the most interested in for example leght of quadrate and supratemporale (and other bones) on maximum size of prey consumed by snake. Which bones are usefull in what environment. More precisly what propotions of snake bones have influence on snake fittnes in particulary environment. I'm also looking for work about sexual dimorphism in Boidae and Pythonidae.
Some interesting works are already done for Natricinae between sexual dimorphism and prey catching environment.
Hibbitts, T.J., Fitzgerald, L.A., 2005. Morphological and ecological convergence in two natricine snakes. Biological Journal of the Linnean Society. 85, 363–371. doi:10.1111/j.1095-8312.2005.00493.x
Vincent, S.E., Moon, B.R., Shine, R., Herrel, A., 2006b. The functional meaning of “prey size” in water snakes (Nerodia fasciata, Colubridae). Oecologia 147, 204–211. doi:10.1007/s00442-005-0258-2,
Shine, R., 1986. Sexual differences in morphology and niche utilization in an aquatic snake, Acrochordus arafurae. Oecologia 69, 260–267.
Borczyk, B., 2014. Allometry of head size and shape dimorphism In Grass Snake (Natrix natrix). Turk. J. Zool. (In press).
Hampton, P.M., 2011. Comparison of cranial form and function in association with diet in natricine snakes. J. Morphol. 272, 1435–1443. doi:10.1002/jmor.10995 - And I'm looking for something similiar for other snakes.
I already read thoose works:
Arnold, S., 1993. Foraging theory and prey-size-predator-size relations in snakes. Ecological Behaviour, New York: McGraw Hill Seigel RA, Collins JT, 87–115.
Aubret, F., Bonnet, X., Harris, M., Maumelat, S., 2005. Sex Differences in Body Size and Ectoparasite Load in the Ball Python, (Python regius). J. Herpetol. 39, 315–320. doi:10.1670/111-02N
Bertona, M., Chiaraviglio, M., 2003. Reproductive biology, mating aggregations, and sexual dimorphism of the Argentine Boa Constrictor (Boa constrictor occidentalis). J. Herpetol. 37, 510–516.
Camilleri, C., Shine, R., 1990. Sexual Dimorphism and Dietary Divergence: Differences in trophic Morphology between Male and Female Snakes. Copeia 3, 649 – 658.
Chiaraviglio, M., Bertona, M., Sironi, M., Lucino, S., 2003. Intrapopulation variation in life history traits of Boa constrictor occidentalis in Argentina. Amphib. Reptil. 24, 65–74.
Feldman, A., Meiri, S., 2013. Length–mass allometry in snakes. Biol. J. Linn. Soc. 108, 161–172. doi:10.1111/j.1095-8312.2012.02001.x
Forsman, A., Shine, R., 1997. Rejection of non-adaptive hypotheses for intraspecific variation in trophic morphology in gape-limited predators. Biology Journal of the Linnean Society 62, 209–223.
Frazzetta, T.H., 1959. Studies on the morphology and function of the skull in the Boidae (Serpentes). Part 1. Cranial differences between Python sebae and Epicrates cenchris. Bulletin of the Museum of Comparative Zoology. 119, 453–472.
Frazzetta, T.H., 1975. Pattern and Instability in the Evolving Premaxilla of Boine Snakes. American Zoologist 15, 469–481. doi:10.1093/icb/15.2.469
Gans, C., 1961. The Feeding Mechanism of Snakes and Its Possible Evolution. American Zoologist 1, 217–227.
Greene, H.W., 1983. Dietary Correlates of the Origin and Radiation of Snakes. American Zoologist doi:http://dx.doi.org/10.1093/icb/23.2.431
Greene, H.W., Burghardt, G.M., 1978. Behavior and phylogeny: constriction in ancient and modern snakes. Science 200, 74–77. doi:10.1126/science.635575
Lee, M.S.Y., Bell Jr., G.L., Caldwell, M.W., 1999. The origin of snake feeding. Lett. Nat. 400.
Luiselli, L., Angelici, F.M., 1998. Sexual size dimorphism and natural history traits are correlated with intersexual dietary divergence in royal pythons (python regius) from the rainforests of southeastern Nigeria. Ital. J. Zool. 65, 183–185. doi:10.1080/11250009809386744
Monteiro, L.R., 1998. Ontogcnetic changes in the skull of Corallus caninus L., 1758 and Corallus enydris L., 1758 (Serpentes: Boidae), an allometric study. SNAKE-NITTAGUN- 28, 51–58.
Pearson, D., Shine, R., Williams, A., 2002. Geographic variation in sexual size dimorphism within a single snake species ( Morelia spilota , Pythonidae). Oecologia 131, 418–426. doi:10.1007/s00442-002-0917-5
Pough, F.H., Groves, J.D., 1983. Specializations of the Body Form and Food Habits of Snakes. American Zoologist 23, 443–454. doi:10.1093/icb/23.2.443
Rodríguez-Robles, J.A., Bell, C.J., Greene, H.W., 1999. Gape size and evolution of diet in snakes: feeding ecology of erycine boas. J. Zool. 248, 49–58. doi:10.1111/j.1469-7998.1999.tb01021.x
Shine, R., 1994. Sexual Size Dimorphism in Snakes Revisited. Copeia 1994, 326. doi:10.2307/1446982
Shine, R., Harlow, P.S., Keogh, J.S., Boeadi, 1998. The influence of sex and body size on food habits of a giant tropical snake, Python reticulatus. Funct. Ecol. 12, 248–258. doi:10.1046/j.1365-2435.1998.00179.x
That is what I have found but I'm still searching. If anyone have some suggestions or doing research about it, I will be very gratefull to hear about it. I'm looking for those informations for my Master degree paper.
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I'm currently working on a project that compares the skull morphology of populations of white-footed mouse (Peromyscus leucopus) based on geographic location. I've been using a copy stand on campus to take images of each skull, but I'm having problems getting crisp, clean images that I can use to clearly identify landmarks. For example, in the attached image the sutures of the skull are difficult to make out. In ventral images differentiating one region form the next has proven very difficult, especially for landmarks at the base of the brain case.
How should I manipulate the light and camera settings to get a high quality image with well defined landmarks? Also, is there a better way to mount skulls for imaging? In the attached image I simply let the skull rest on the block with the incisors hanging over the edge. Finally, for taking lateral and ventral photos of the skull what mounting techniques should I use?
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The cheapest way is staged photography using a reflex camera on a tripod and a ring flash.
I use a Canon 550D with a Metz MB 15 MS-1 Makroslave digital ring flash; entirely mounted on a Cullmann NANOMAX 200T traveler tripod to perform stacking photography using an Laptop and Helicon Remote and Helicon Focus software (HeliconSoft Ltd., Kharkov, Ukraine).
I don't know how much money you can spend on that? This is a really proper way to make staged photos. The Software is comparable cheap and works really well!
If you can't spend so much money, the most important thing is light!
Try to buy or borrow a ring flash and use a uniform background (not as on your uploaded picture).
Hope that'll help a little bit!
Cheers,
Sebastian
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I have microCT scans of different feather shafts (non-circular, not really hollow, with clear heterogeneity in material composition); I want to get accurate calculations of the 2nd moment of area without the standard assumptions of regular geometry. I'm leaning towards the BoneJ plugin for ImageJ, and would love thoughts on this or any other suggestions.
Because there are also differences in resolution between feathers (feathers of different sizes were scanned in the same container), I am also wondering if relatively lower resolution of the smaller diameter feathers is a limitation for either calculating or automating.
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Firstly, BoneJ is probably your best solution. The nice part about BoneJ is you can align your feather shaft first using the moments of inertia function prior to calculating second moment of area. This will be important because your feathers probably weren't all aligned exactly the same in the container when you scanned them. Also you can base your segmentation (feather vs. non-feather) on the histogram to make sure its repeatable and automated. This will be important if you're saying there is distinct heterogenity in the composition.
I've had a similar situation with long bone CT scans, in terms of worrying about your measurement error increasing with smaller objects. The simplest test is just to measure a property with callipers, and then compare with the same property from CT. Hopefully your errors will stay proportionally the same. The better test would be to do a convergence analysis on your smallest feather. Scan it several times at decreasing resolution, measuring the same property from the same location every time. Convergence is reached once your values plateau and increasing resolution doesn't affect your propery any more.
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I realize that this question basically boils down to "which species had the brain that was least small", but given the amount of geological time and diversity present in these animals, one would think that there would be at least some variation in the group. More specifically, I have been trying to see if the size and shape of the braincase have any effect on the morphology of the sauropod skull (i.e., in the position of the eyes, etc.). Hence brain-to-skull size, rather than "largest brain relative to body size" If anyone knows which diplodocoid taxa is known to have the largest brain relative to its skull size, that would be a huge help too.
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Hi Russell,
this is a difficult question to answer due to several reasons, as you probably know yourself as well: 1) skulls are very rare in sauropods, 2) complete skulls are even rarer (mostly the braincase is disassociated from the snout elements), 3) complete, undeformed skulls are practically non-existent (I know of 3 or 4 in diplodocoids, where deformation is PROBABLY minimal), and 4) how do you define braincase and skull size?
My best guess in getting this kind of data for diplodocoids would be to ask Larry Witmer or someone in the Emily Rayfield group. These have probably the most extensive sample of complete, CT-scanned, diplodocoid skulls, where you could get this info from. If you use linear measurements of external braincase features to measure braincase size I could also help you with Kaatedocus, of which a surface scan exists. However, this obviously won't give volumetric braincase data.
I hope this helps! If you need a comprehensive list of sauropod skulls, check Whitlock et al. 2010 on the juvenile Diplodocus, and Poropat & Kear 2013 on Euhelopus.
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I am interested in calculating the second (and polar) moment of area for some cross-sections of appendicular bones that do not have standard hollow, circular geometries, and heard that there could be some complications to interpreting the second moment of area based on more complex geometries. Could anyone recommend any references that discuss calculating the second moment of area from geometries that may not follow standard beam theory? Or modifications to standard beam theory?
Thank you in advance!
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No problem Sandy.
I spent a lot of time on 2D cross sectional analysis of bones in the past but I never found a good application for it. I am just happy if someone else has.
Sorry about the confusion with the notation. I use I(eta) and I(xsi) for the maximum and minimum principal second area moments respectively. I suspect that that corresponds to the Imax and Imin in ShapeDesigner. You should probably verify this by analysing a cross section with known properties (from some text book) when you start using ShapeDesigner.
Good luck with this work.
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I am wondering if it would be possible for a ruminant to grow as large as some of the largest land mammals to have lived. If it is not possible, one of the constraints might be the functionality of such a large rumen. Or what other factors are there to consider as well?
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There is a paper by Clauss et al. (2003) about body size limitations in living and fossil ruminants:
They find only one fossil group possibly surpassing maximum body size in extant ruminants of about 1000 kg: sivatheriine giraffids.
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Is there a direct advantage in having a non-localized respiratory system (tracheae) instead of lungs (in Arachnida)?
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One idea: Perhaps evolution of tracheae cannot be explained through a physical advantage but by constraints of body morphology, e.g. tracheae evolved in a tracheatan ancestor with many similar segments (metamerism) whereas evolution of lungs occurred in arachnids with a comparatively derived (spider-like) morphology.
(Perhaps insects would actually be better off with lungs but lung evolution was inhibited by the presence of tracheae, so insects were stuck with the latter.)
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Can anyone help me with the identification keys (morphology) of AMF spores?
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Hmmm. Noticed my counting went wrong in my last answer. I can count up to five -- honestly :-)
It may be worth you reading the paper by Redecker et al. 2013 (Redecker, D., Schüßler, A., Stockinger, H., Stürmer, S. L., Morton, J. B., & Walker, C. (2013). An evidence-based consensus for the classification of arbuscular mycorrhizal fungi (Glomeromycota). Mycorrhiza, 23(7), 515–31. doi:10.1007/s00572-013-0486-y). Can't put it on ResGate for copyright reasons. But this does deal mostly with higher level classifications. Look also at our website amf-phylogeny.com where many original species descriptions can be found as pdf files. You will, I am afraid, notice that several files are not available as the authors and/or journals would not give us permission to add them. The nomenclature is not quite up to date there, but we will try to do it as soon as possible (neither Arthur Schuessler nor myself have any funding for this work).
I fear very much that relating old and new literature will prove very difficult indeed. Few researchers keep voucher specimens, even of cultures, let alone of 'species' they identify from field collections. Lists of species are published without any evidence of the veracity of identification. Careful and detailed re-descriptions and definitions of individual species are difficult or impossible to publish in high-quality journals (not of interest to the general reader, or so it seems). But I must not go on as I am accused by some of my peers of 'ranting' ... (I am indeed old and very cranky).
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I have recently seen a Black Vulture (Coragyps atratus) with an odd beak. It was seen in a polluted mangrove area near Rio de Janeiro. Its beak was longer and curvier than of others. So this intriguingly-shaped beak made me think of the reasons that some individuals would devolop and survive into adulthood with malformed beaks in general.
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Hi Lorian,
Maybe this paper or some of his references will help you. The problem is it is in Spanish.
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Especially for complex terms such as 'postero-dorsal rim of pygophore [genital chamber]'. Is there a general reference or a set of guidelines to look up?
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Hi Gao,
The correct name it is aedeagus and you can see this book "Taxonomist's Glassary of Gentitalia in Insects by S. L. Tixen.
Best regards
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I'm curious about the type of life that saber toothed animals had and what was their teeth main function. Watching cranial anatomy it seems that their teeth had a very important function. This feature evolved independently over the geological time and in different animal orders.
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The notion that their canines look like butcher knives and therefore they might have been scavengers is a very interesting one. However, the key to reconstructing the behavior of extinct species is to look not only at the morphology as functional units but to look at the morphology and try to find modern species with that same morphology and infer the behavior from that. This is called "the comparative method." Unfortunately, the problem with sabertooths (and why so many of us obsess about them!) is that none still exist. So we have to look at other more subtle pieces of their morphology to make deductions.
Indeed the canines do look a bit like butcher knives, but the question is, if your hypothesis is that this would indicate scavenging, do modern scavengers have knife-like teeth? The answer is actually just the opposite: hypercarnivores (flesh specialists) have very sharp teeth while species that tend toward scavenging tend to need to eat less optimal parts of carcasses (because the initial hunters eat the flesh) and therefore have teeth adapted more toward bone crunching like the hyaenids (though these guys are great hunters too) or have more diverse teeth (including slicing, crushing and grinding teeth) like many canids. Sabertooths don't exhibit either of these morphologies.
The observation that Smilodon clearly "scavenged" prey trapped in the tar is another great one. Indeed this is probably indisputable. However, it does NOT imply that they were dedicated or even predominant scavengers. ALL carnivores will take prey opportunistically. In fact, even cows will eat flesh if they come upon it. Heck, if I were in LA back then, I'd eat a trapped mammoth even though I am personally clearly more of a gatherer than a hunter!
As for placing a precise bite, it's certainly true that struggling prey would be the biggest danger to that tooth. I believe that the strong front limbs were adapted for the purpose of securing the prey to avoid this. Regardless, the tooth is not really good for anything other than killing - all canines are only good for killing or fighting actually. Even though the saber tooth looks like a butcher knife, the real butchering teeth are the premolars and carnassials. No carnivores use their canines for meat slicing.
I'm not sure why you think sabertooths would be slower than a modern felid with the same body mass. They certainly were not cursors like cheetahs (but then, nothing alive really is!), not were they even as cursorial as modern generalized felids (e.g., lions), but with a body build similar to jaguars, there's no reason to believe they were slower then them.
Lastly, you asked about the explanation for the extensively healed wounds; I have spent a good amount of time in the La Brea collection (actually I'm going back there in a couple of weeks) and I just don't think that population displays extensive healing. Keep in mind two things: 1) those animals were in rough shape in general - if you haven't read the "tough times at La Brea" paper you should! 2) There are literally thousands of individuals in that sample. If you looked at a sample of tigers that was as large as that, I would bet that you could find some individuals with as extensive healed wounds. Despite this, we know that tigers are not pack animals. 3) Pack animals don't really provision their sick like this. Have you EVER seen a sick lion? Wolf? Hunting dog? When a carnivore becomes injured, they are a liability to their pride/pack/group. The males are killed immediately by the next dude in line and the females are probably not likely to be reproductive any more (healing wounds takes energy away from growing babies) and are therefore evolutionarily not particularly useful. Aside from love - a human emotion - why keep them in the group?