[Paleontology • 2017] Borealopelta markmitchelli • An Exceptionally Preserved Three-Dimensional Armored Dinosaur Reveals Insights into Coloration and Cretaceous Predator-Prey Dynamics ---ScRaBBlE

Borealopelta markmitchelli 

Brown, Henderson, Vinther, Fletcher, Sistiaga, Herrera & Summons, 2017

 DOI: 10.1016/j.cub.2017.06.071 

Highlights

• A new armored dinosaur is described based on an exceptionally preserved specimen

• Abundant in situ osteoderms with keratinous sheaths and scales are preserved

• Reddish-brown coloration and crypsis in the form of countershading are indicated

• Crypsis indicates strong predation pressure on this large, heavily armored dinosaur

Summary

Predator-prey dynamics are an important evolutionary driver of escalating predation mode and efficiency, and commensurate responses of prey. Among these strategies, camouflage is important for visual concealment, with countershading the most universally observed. Extant terrestrial herbivores free of significant predation pressure, due to large size or isolation, do not exhibit countershading. Modern predator-prey dynamics may not be directly applicable to those of the Mesozoic due to the dominance of very large, visually oriented theropod dinosaurs. Despite thyreophoran dinosaurs’ possessing extensive dermal armor, some of the most extreme examples of anti-predator structures, little direct evidence of predation on these and other dinosaur megaherbivores has been documented. Here we describe a new, exquisitely three-dimensionally preserved nodosaurid ankylosaur, Borealopelta markmitchelli gen. et sp. nov., from the Early Cretaceous of Alberta, which preserves integumentary structures as organic layers, including continuous fields of epidermal scales and intact horn sheaths capping the body armor. We identify melanin in the organic residues through mass spectroscopic analyses and observe lighter pigmentation of the large parascapular spines, consistent with display, and a pattern of countershading across the body. With an estimated body mass exceeding 1,300 kg, B. markmitchelli was much larger than modern terrestrial mammals that either are countershaded or experience significant predation pressure as adults. Presence of countershading suggests predation pressure strong enough to select for concealment in this megaherbivore despite possession of massive dorsal and lateral armor, illustrating a significant dichotomy between Mesozoic predator-prey dynamics and those of modern terrestrial systems.

 Systematic Paleontology

Dinosauria Owen, 1842  

Ornithischia Seeley, 1888  

Ankylosauria Osborn, 1923  

Nodosauridae Marsh, 1890  

Borealopelta markmitchelli gen. et sp. nov. 

Etymology: The generic name Borealopelta is derived from “borealis” (Latin, “northern”) and “pelta” (Greek, “shield”), in reference to the northern locality and the preserved epidermal scales and dermal osteoderms. The specific epithet markmitchelli honors Mark Mitchell for his more than 7,000 hours of patient and skilled preparation of the holotype.

An illustration of Borealopelta markmitchelli. The study suggests that it displayed a camouflage effect known as counter-shading.

 Illustration: Julius Csotonyi/Courtesy of the Royal Tyrrell Museum of Palaeontology, Canada. 

 Illustration: Robert Nicholls 

 Illustration: Davide Bonadonna

Figure 1. Photographs of the Holotype of Borealopelta markmitchelli, TMP 2011.033.0001 Top: anterodorsolateral view; bottom: anterodorsal view. Scale bar, 10 cm. 

Holotype: The holotype is Royal Tyrrell Museum of Palaeontology (TMP) 2011.033.0001: an articulated specimen preserving the head, neck, most of the trunk and sacrum, a complete right and a partial left forelimb and manus, partial pes (Figure 1). In situ osteoderms and nearly complete soft tissue integument are preserved across dorsal and lateral surfaces of the axial skeleton, posterodorsal surface of forelimbs, and plantar surfaces of a manus and a pes. Specimen is preserved in multiple large blocks, including slabs and counter-slabs in the sacral region.

Locality and Horizon: Suncor Millennium Mine, Fort McMurray, Alberta, Canada. Wabiskaw Member, Clearwater Formation, Aptian stage. Detailed locality data are available at Royal Tyrrell Museum of Palaeontology.

Diagnosis: A nodosaurid ankylosaur characterized by the following autapomorphies (∗) and suite of characters [character/state]: cranial: dorsal skull ornamentation expressed as a large hexagonal dermal plate in frontoparietal region and multiple (>20) small dermal plates in frontonasal region∗; external nares excluded from view dorsally (shared with Pawpawsaurus) [16:1]; supraorbital ornamentation forming sharp lateral rim dorsal to orbits (shared with Gargoyleosaurus and Kunbarrasaurus) [38:2]; jugal (suborbital) horn triangular with pointed apex (shared with Gastonia, Gargoyleosaurus, and Polocanthus); jugal (suborbital) horn base longer than orbit length∗; osteoderms: cervical and thoracic osteoderms form continuous (abutting) transverse rows completely separated by continuous transverse rows of polygonal basement scales; parascapular spine is the largest osteoderm, recurved, and projects posterolaterally and horizontally (potentially shared with Sauropelta); osteoderm count for transverse rows: cervicals: C1-3, C2-3, C3-3, transition: TR-2, thoracic: T1-6∗; third and sixth transverse thoracic osteoderm rows expressed medially but pinch out laterally∗.

The new taxon can be further differentiated from Pawpawsaurus based on: dermal plate in frontonasal region (central dermal plates) flat; absence of ciliary osteoderm. Can be further differentiated from Sauropelta based on: parietals flat to slightly convex; cervical half ring has 4–6 osteoderms only; medial cervical osteoderms subequal, hexagonal, and bear prominent median ridge with posterior margin projecting beyond the basal footprint.

Figure 2: Schematic Line Drawing of TMP 2011.033.0001, the Holotype of Borealopelta markmitchelli, Illustrating Preservation of the Different Tissue Types (A) Schematic of complete specimen in dorsal view. (B and C) Skull in dorsal (B) and left lateral (C) views. (D) Close-up view of the neck, illustrating alternating cervical osteoderm bands (and preserved keratinous sheaths) and polygonal scales. (E) Close-up view of flank illustrating lateral thoracic osteoderms (with keratinous coverings) and polygonal scales. (F) Close-up view of sacral shield counterpart illustrating osteoderms and scales. (G) Close-up view of antebrachium including osteoderms and keratinous coverings. (D’–G’) Interpretive line drawings of the corresponding panels (D)–(G). Scale bars in (B)–(G), 10 cm.

Figure 3: Time-Calibrated Strict Consensus Tree Showing Position of Borealopelta markmitchelli within Ankylosauria, with Representative Well-Preserved Ankylosaurs Shown Above Bottom: time-calibrated strict consensus tree illustrating position of Borealopelta markmitchelli within Ankylosauria scaled to Jurassic and Cretaceous stages. Top: line drawings of representative well-preserved ankylosaur specimens with in situ armor and/or skin. Scale bars, 1 m.
(A) Kunbarrasaurus, QM F18101. (B) Euoplocephalus, NHMUK 5161. (C) Sauropelta, AMNH 3035 and 3036 composite. (D) Borealopelta, TMP 2011.033.0001 (this study). (E) Edmontonia, AMNH 5665.

Figure 4:  Chart Illustrating the Loss of Countershading as Body Mass Increases in Terrestrial Mammal Herbivores Chart includes pooled data for artiodactyls, perissodactyls, and proboscideans divided into body-mass bins, showing relative proportion of species that exhibit countershading. The diagonally hatched area represents the mass above which significant predation of adults does not occur. Animals illustrated above chart are representative taxa within each mass bin; species names in italics at top indicate body masses of the largest carnivores.

The Making of a Most Extraordinary Fossil

NationalGeographic.com 

The Making of a Most Extraordinary Fossil

NationalGeographic.com

on.natgeo.com/2r02aW7

Caleb M. Brown, Donald M. Henderson, Jakob Vinther, Ian Fletcher, Ainara Sistiaga, Jorsua Herrera and Roger E. Summons. 2017. An Exceptionally Preserved Three-Dimensional Armored Dinosaur Reveals Insights into Coloration and Cretaceous Predator-Prey Dynamics. Current Biology. DOI: 10.1016/j.cub.2017.06.071

Despite heavy armor, new dinosaur used camouflage to hide from predators  eurekalert.org/e/7ZWJ via @CellPressNews @EurekAlert

http://videnskab.dk/naturvidenskab/ekstremt-velbevaret-dinosaur-vidner-om-uhyggelig-fortid

It's Official: Stunning Fossil Is a New Dinosaur Species  on.natgeo.com/2vx0wxD via @NatGeo

This Is the Best Dinosaur Fossil of Its Kind Ever Found on.natgeo.com/2r02aW7 via @NatGeo

Discover How This Dinosaur Became an Extraordinary Fossil  NationalGeographic.com/magazine/2017/06/making-of-a-dinosaur-fossil-nodosaur-illustrations

Heavily armoured dinosaur had ginger camouflage to deter predators – study  theguardian.com/science/2017/aug/03/heavily-armoured-nodosaur-ginger-camouflage-predators-borealopelta-markmitchelli

Alberta museum unveils world's best-preserved armoured dinosaur  theguardian.com/science/2017/may/15/alberta-canada-museum-unveils-best-preserved-armoured-dinosaur-in-the-world-nodosaur

ติดอยู่ในกาลเวลา  ngthai.com/animals/1703 via  เนชันแนล จีโอกราฟฟิก (National Geographic) ฉบับภาษาไทย

  

  

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل

من هنا

او

من هنا

شاهد هذا الفيديو القصير لطريقة التحميل البسيطة

منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات

كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا

شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا

رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا

تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Paleontology • 2017] Zuul crurivastator • A New Ankylosaurine Dinosaur from the Judith River Formation of Montana, USA, Based On An Exceptional Skeleton with Soft Tissue Preservation ---ScRaBBlE

Zuul crurivastator 

 Arbour & Evans, 2017  

ROM.on.ca  DOI: 10.1098/rsos.161086 

Abstract

The terrestrial Judith River Formation of northern Montana was deposited over an approximately 4 Myr interval during the Campanian (Late Cretaceous). Despite having been prospected and collected continuously by palaeontologists for over a century, few relatively complete dinosaur skeletons have been recovered from this unit to date. Here we describe a new genus and species of ankylosaurine dinosaur, Zuul crurivastator, from the Coal Ridge Member of the Judith River Formation, based on an exceptionally complete and well-preserved skeleton (ROM 75860). This is the first ankylosaurin skeleton known with a complete skull and tail club, and it is the most complete ankylosaurid ever found in North America. The presence of abundant soft tissue preservation across the skeleton, including in situ osteoderms, skin impressions and dark films that probably represent preserved keratin, make this exceptional skeleton an important reference for understanding the evolution of dermal and epidermal structures in this clade. Phylogenetic analysis recovers Zuul as an ankylosaurin ankylosaurid within a clade of Dyoplosaurus and Scolosaurus, with Euoplocephalus being more distantly related within Ankylosaurini. The occurrence of Z. crurivastator from the upper Judith River Formation fills a gap in the ankylosaurine stratigraphic and geographical record in North America, and further highlights that Campanian ankylosaurines were undergoing rapid evolution and stratigraphic succession of taxa as observed for Laramidian ceratopsids, hadrosaurids, pachycephalosaurids and tyrannosaurids.

KEYWORDS: Ornithischia, Thyreophora, Ankylosauria, Ankylosaurinae, Cretaceous, Campanian

Systematic palaeontology

Dinosauria Owen, 1842 

Ornithischia Seeley, 1887 

Thyreophora Nopcsa, 1915 

Ankylosauria Osborn, 1923 

Ankylosauridae Brown, 1908 

Ankylosaurinae Brown, 1908 

Ankylosaurini Arbour and Currie, 2016

ZUUL gen. nov.

Type and only known species: Zuul crurivastator gen. et sp. nov.

Etymology: The generic name refers to Zuul the Gatekeeper of Gozer, a fictional monster from the 1984 film Ghostbusters, and the species epithet, crurivastator, combines crus (Latin) for shin or shank, and vastator (Latin) for destroyer, in reference to the sledgehammer-like tail club.

Holotype: ROM 75860.

Diagnosis: Differs from all ankylosaurids in the possession of the following autapomorphies: imbricated, peaked frontonasal and frontoparietal caputegulae; prominent longitudinal furrows on the lateral surface of the squamosal horn; lateral caudal osteoderms along the tail club (excluding the knob osteoderms) are strongly concave on the leading edge with posteriorly offset apices; tail club knob dorsoventrally flat, with height to length ratio less than 0.20. Zuul can be further differentiated from other ankylosaurins in the following traits: possesses pyramidal prefrontal, frontoparietal and middle supraorbital caputegulae (unlike the conical caputegulae in Nodocephalosaurus and Talarurus); squamosal horns extend posteriorly well past the nuchal shelf, similar to Scolosaurus but unlike Anodontosaurus, Euoplocephalus, or Ziapelta; postocular caputegulae small and sparsely distributed, similar to Scolosaurus but unlike Anodontosaurus, Euoplocephalus or Ziapelta. Caudal osteoderms lateral to tail club handle are proportionately larger and more sharply pointed than in ankylosaurines from the Nemegt Formation of Mongolia.

Life restoration of Zuul crurivastator.

Illustration: Danielle Dufault 

Zuul crurivastator size compared to an African elephant Loxodonta africana.

Illustration: Danielle Dufault  

Holotype locality: Approximately 5 km northwest of the John Wodarz Bridge, in badlands exposures of the Judith River Formation outcropping along the north side of the Milk River Drainage near the City of Havre, Montana (Section 35, Township 33N, Range 15E). GPS coordinates for the quarry are reposited at the Royal Ontario Museum. The site was originally designated Theropoda Exp LLC Locality LC02(Q).

Stratigraphic horizon and age: Coal Ridge Member of the Judith River Formation. The Coal Ridge Member was deposited between 76.2 and 75.2 Ma.

Figure 6. Overview of the tail of Zuul crurivastator ROM 75860 in dorsal view, with insets of detailed anatomy.
 (a) Field of ossicles in the anterior portion of the tail. (b) Detail of the neural arches of the handle caudal vertebrae, and ossified tendons. (c) Left caudal osteoderm from the seventh pair. (d) Preserved epidermal sheath on the right caudal osteoderm from the second pair. (e) Preserved epidermal sheath on the right caudal osteoderm from the third pair. (f) Epidermal scales lacking bony cores, arranged in a transverse row at the third pair of caudal osteoderms. (g) Close-up of the tail club knob. 

The knob of bone forming the sledgehammer-like tip of the tail in Zuul crurivastator.

photo: Brian Boyle/Royal Ontario Museum  

Conclusion: 

ROM 75860 represents a new ankylosaurine genus and species, Zuul crurivastator from the Judith River Formation. The holotype specimen is one of the most complete dinosaur skeletons from this formation, and is the first ankylosaurid skeleton described from this unit. Remarkably, ROM 75860 is the first ankylosaurin skeleton known with a complete skull and tail club, and it is the most complete ankylosaurid ever found in North America. The presence of abundant soft tissue preservation across the skeleton, including in situ osteoderms, skin impressions and dark films that probably represent preserved keratin, make this exceptional skeleton an important reference for understanding the evolution of dermal and epidermal structures in this clade. The recognition of Z. crurivastator from the Judith River Formation fills a gap in the ankylosaurine stratigraphic and geographical record and further highlights that Laramidian ankylosaurines were undergoing rapid evolutionary rates and stratigraphic turnover as observed for Laramidian ceratopsids, hadrosaurids, pachycephalosaurids and tyrannosaurids. The excellent preservation of ROM 75860 and the abundant diversity represented elsewhere in the same quarry highlight the potential for significant new fossil discoveries in the upper Judith River Formation and emphasize the need for continued work in this historically significant geological unit.

  

Victoria M. Arbour and David C. Evans. 2017. A New Ankylosaurine Dinosaur from the Judith River Formation of Montana, USA, Based On An Exceptional Skeleton with Soft Tissue Preservation. Royal Society Open Science. DOI: 10.1098/rsos.161086

Zuul, Destroyer of Shins
rom.on.ca/en/collections-research/research-community-projects/zuul

Meet Zuul, destroyer of shins - the 75m-year-old 'Ghostbuster' dinosaur theguardian.com/science/2017/may/10/meet-zuul-destroyer-of-shins-the-75m-year-old-ghostbuster-dinosaur

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل

من هنا

او

من هنا

شاهد هذا الفيديو القصير لطريقة التحميل البسيطة

منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات

كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا

شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا

رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا

تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Paleontology • 2017] Borealopelta markmitchelli • An Exceptionally Preserved Armored Dinosaur reveals the Morphology and Allometry of Osteoderms and their Horny Epidermal Coverings ---ScRaBBlE

Borealopelta markmitchelli 

Brown, Henderson, Vinther, et al., 2017

Brown​. 2017.  DOI:  10.7717/peerj.4066  @Brown_Caleb_M

Abstract

Although the evolution and function of “exaggerated” bony projections in ornithischian dinosaurs has been subject to significant debate recently, our understanding of the structure and morphology of their epidermal keratinized coverings is greatly limited. The holotype of Borealopelta, a new nodosaurid ankylosaur, preserves osteoderms and extensive epidermal structures (dark organic residues), in anatomic position across the entire precaudal length. Contrasting previous specimens, organic epiosteodermal scales, often in the form of horn-like (keratinous) sheaths, cap and exaggerate nearly all osteoderms, allowing for morphometric and allometric analyses of both the bony osteoderms and their horny sheaths. A total of 172 osteoderms were quantified, with osteoderm spine length and height being positively allometric with respect to basal length and width. Despite tight correlations between the different measures amongst all other osteoderms, the large parascapular spines represent consistent outliers. Thickness and relative contribution of the keratinized epiosteodermal scales/sheaths varies greatly by region, ranging from 2% to 6% for posterior thoracics, to ∼25% (1.3×) for the parascapular spines—similar to horn sheaths in some bovid analogues. Relative to the bony cores, the horny portions of the spines are strongly positively allometric (slope = 2.3, CI = 1.8–2.8). Strong allometric scaling, species-specific morphology, and significant keratinous extension of the cervicoscapular spines is consistent with elaboration under socio-sexual selection. This marks the first allometric analysis of ornithischian soft tissues.

  

Figure 1: Dorsal view of TMP 2011.033.0001, showing both photocomposite and schematic line drawing.
 (A) Photocomposite dorsal view of TMP 2011.033.0001. (B) Schematic line drawing of (A) showing osteoderm regions by color. (C) Inset showing constituent blocks of TMP 2011.033.0001, and their relative position within a body outline in dorsal view. Photocomposite (A), created using separate, orthogonal images of blocks A–C, D, E, F–I, and J and combined digitally to reduce parallax. Blocks F, G, H, and I represent reflected counterpart.

  

Figure 2: Single dorsal photograph of TMP 2011.033.0001.
Sacral region represents original part—reflected counterpart shown in Fig. 4. Scale equals 1 m.

Figure 3: Interpretive scientific illustration of TMP 2011.033.0001 in dorsal view.
Sacral region represents original part—reflected counterpart shown in Fig. 4. Scale equals 1 m.

Figure 4: Composite dorsal view of TMP 2011.033.0001.
Photocomposite created using separate images of blocks A–C, D, E, F–I, and J (see Fig. 1) and combined digitally to both reduce parallax and remove gaps. Blocks F, G, H and I represent reflected counterpart of sacral part in Fig. 2. Photographs of individual blocks were digitally modified (brightness, contrast, etc.) to removed different lighting conditions, and to illustrate an average composite of the entire specimen. Scale equals 1 m.

Figure 15: Comparisons of the size of the bony core and keratinous sheath of the parascapular spine of Borealopelta to modern bovid and squamate analogues.
(A) Absolute size of the bone core (horncore or osteoderm) (yellow) and the overlying keratinous/horn sheath (grey) for the parascapular spine of TMP 2011.033.0001 (top) as well as averages for several bovid and squamate taxa (lower).
 (B) Schematic representations of the relative bony and keratinous components of select spines/horns (adjusted to same size). Data for Oreamnos americanus (n = 6, 20) and Oreamnos harringtoni (n = 10, 13) from Mead & Lawler (1995), Bos (n = 18) from Grigson (1975), Antilocapra (n = 3) and Bison (n = 18) from Borkovic (2013), Ovis nivicola (n = 2), Ovis dalli (n = 2), Ovis ammon (n = 2), Ovis canadensis nelsoni (n = 5), Ovis canadensis canadensis (n = 8), Capra ibex sibirica (n = 4) and Capra ibex ibex (n = 5) from Bubenik (1990), Trioceros (n = 1) from TMP 1990.007.0350, Phrynosoma solare (n = 1) from LACM 123351, and P. asio (n = 1) from WLH 1093.

Conclusion

The combined results showing that the osteoderm spines, and their keratinous coverings, are positively allometric (regionally); and that the anterior portion of the osteoderm series is both highly variable and has species specific morphology, provided new insights into the function and evolution of these structures. Similar results have been obtained from analysis of the exaggerated structures of most other ornithischian clades: Hadrosauridae (Dodson, 1975; Evans, 2010; McGarrity, Campione & Evans, 2013), Ceratopsia (Currie et al., 2016; Dodson, 1976; Hone, Wood & Knell, 2016; Lehman, 1990), Pachycephalosauria (Horner & Goodwin, 2009; Schott et al., 2011). These results in other ornithischian clades have been used to support the hypothesis that these exaggerated structures may have functioned, and evolved, in the context of socio-sexual selection (Hone, Wood & Knell, 2016; Hopson, 1975; Sampson, 1997). Similar hypotheses have been proposed for thyreophoran spines and plates (Carpenter, 1998; Hopson, 1977; Main et al., 2005; Padian & Horner, 2011), but until now had lacked commensurate morphometric backing. This argument is strengthened further when the parascapular spine is considered. Not only does this element show a different pattern of scaling than the rest of the series, but the absolute sizes of the keratin sheath and bony core are similar to the horns of extant bovids, and the relative sizes similar to the horns of some extant squamates, both of which are thought to function in socio-sexual display (Bustard, 1958; Farlow & Dodson, 1975; Geist, 1966). Combined with recent evidence suggesting this spine may, in life, have been pigmented differently than the rest of the osteoderms (Brown et al., 2017), this suggests this spine may have function as a visual socio-sexual display signal with conspecifics.

Caleb M. Brown​. 2017. An Exceptionally Preserved Armored Dinosaur reveals the Morphology and Allometry of Osteoderms and their Horny Epidermal Coverings. PeerJ. 5:e4066.  DOI:  10.7717/peerj.4066

New research analyses body armour of Borealopelta  RoyalTyrrellMuseum.wordpress.com/2017/11/29/new-research-analyses-body-armour-of-borealopelta/ via @RoyalTyrrell

 twitter.com/Brown_Caleb_M/status/935896521182031872

   

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل

من هنا

او

من هنا

شاهد هذا الفيديو القصير لطريقة التحميل البسيطة

منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات

كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا

شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا

رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا

تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.