Some beetles, lizards have horn-like structures, but mammals have the most diverse horns without doubt. Humans have cervical vertebrae as well, though they are obviously much smaller and shorter than the cervical vertebrae found in giraffes. The BWA-MEM programme was executed with default parameters and statistics were extracted using the samtools stats tool. 9, 62296232 (2010). The authors declare no competing financial interests. The yak genome and adaptation to life at high altitude. Assembly algorithms for next-generation sequence data. Luo, R. et al. For example, homologous structures include the limbs of mammals, such as bats, lions, whales . Functional classification of positively selected genes was achieved using PANTHER classification of Biological Process ontology terms65. The human vermiform appendix is a vestigial structure; it no longer retains its original function. Seventy genes were identified that exhibited MSAs based on amino acid sequence divergence as evaluated by neighbour-joining phylogenetic analysis of mammalian orthologous proteins, enrichment of nonsynonymous substitutions, unique amino acid substitutions at sites otherwise fixed in mammals, substitutions predicted to cause functional changes by Polyphen2 analysis and substitutions under positive selection. The growth of the antlers has several phases: A, B, C: 1, 15 y 30 days of growht. 24, 12191228 (2007). Cytogenet. These data were analysed extensively on the Galaxy platform66,67 to determine enrichment of dN and dN/dS () in giraffecattle as compared with okapicattle. African J. Biotechnol. Branch-site models were used to identify positive selection acting on giraffe versus cattle, okapi and gerenuk. The pyramidalis muscle is a paired, triangular-shaped muscle that, when present, is located in the lower abdomen between the muscle and muscle sheath of the rectus abdominis. and E.I. Giraffe genome sequence reveals clues to its unique morphology and physiology. Share: About TED-Ed Best of Web 1), substantially less than the previous estimate of 16 mya (refs 19, 20), which was based on mitochondrial DNA sequence comparisons. In addition, HOXB13, which regulates angiogenic and posterior axial skeletal development, shows high amino acid sequence divergence in giraffe and okapi compared with other mammals (Supplementary Table 4). A)the spider B) giraffe C) T. rex D) giraffe & bird (equally) . Bedoya-Reina, O. C. et al. It needs three requirements to act: Over the years these changes are accumulated until the genetic differences are so big that some populations may not mate with others: a new species has appeared. 80, 269302 (2005). 1). This similarity suggests human and giraffe necks are. Lankester, R. On certain points in the structure of the cervical vertebrae of the okapi and the giraffe. A. Mol. Am. Examples of how to use "vestigial structure" in a sentence from Cambridge Dictionary. Res. Genet. Douglas R. Cavener. Physiol. Evolution can be observed in beings with a very high reproduction rate, for example bacteria, since mutations accumulate more quickly. (34) $4.95. Check outthis spectacular dispute between two Canadian mouflons: There are species with small antlers but highly developed tusks, despite being herbivores. FGFRL1 in mammals lacks a tyrosine kinase domain essential for downstream FGF signalling and acts as a competitive inhibitor of the nascent FGF receptors23. Mol. The MSA genes that are not known to be related to the regulation of skeletal, cardiovascular, or neural development are listed (right box). Biol. They are permanent, not branched and they are always covered with hair and skin. Article Bock, F. et al. and P.M. performed the genome assemblies. Vestigial structures can provide insights into an organism's ancestry. They are an accumulation of corneous fibers, resembling a thick hair, although they are not true hairs. The giraffe and okapi sequence data were also used to generate a draft genome assembly with a total length of 2.9 and 3.3Gb for giraffe and okapi, respectively (Supplementary Table 2). Solounias, N. The remarkable anatomy of the giraffes neck. Homologous . To obtain Hassanin, A. et al. This ensured correction for frame shifts indels, as it was noted that some sequences were of draft quality and may have some sequencing errors. The images show the wings of two different organisms. Genetic variability allows natural selection act. 284, 3393933948 (2009). In contrast, species with larger antlers do not have these developed tusks. IS IT TRUE THAT ORGANISMS ADAPT TO THE ENVIRONMENT AND ARE DESIGNED FOR LIVING IN THEIR HABITAT? 11 Jun 2022. Proc. Approximately 400 genes exhibiting exceptionally higher dN or dN/dS values in giraffecattle dyad were further analysed in detail including (a) Polyphen2 analysis21 to identify amino acid substitutions predicted to be probably damaging; (b) Unique Substitution Analysis to identify unique amino acid substitutions in giraffe at fixed sites in eutherians, and to determine which genes have a statistically significant excess of unique substitutions at fixed sites, unique substitutions were manually curated from BLAST alignments; and (c) protein phylogenetic tree analysis using neighbour-joining method to identify genes that exhibit a high degree of divergence in giraffe as assessed by relative branch lengths. With new scientific advances, his theory has been improved and detailed, but more than 150 years later, nobody has been able to prove it wrong, just the contrary. Yang, Z., Wong, W. S. & Nielsen, R. Bayes empirical bayes inference of amino acid sites under positive selection. 2002. When growth is complete the horn nucleus ossifies and fuses with the frontal bones of the skull. D.R.C. al. 59). Volatile fatty acids production in ruminants and the role of monocarboxylate transporters: a review. performed the whole-genome sequencing. 2, 150393 (2015). Finally, gaps in scaffolds were filled using GapCloser (v1.12) with default parameters. Several of these genes encode well-known regulators of skeletal, cardiovascular and neural development, and are likely to contribute to giraffes unique characteristics. Integr. CAS 2022 Beckoning-cat.com. Here are six of the more surprising examples of human vestigiality. The same applies to other species, in case you have asked yourself, if amphibians come from fish, why are there still fish?. As maximum likelihood methods designed to detect episodes of positive selection are sensitive to taxa sample size63, we re-analysed the initial PSG candidates list by including the orthologues of all mammals for which high-quality sequence data were available (1045 species). Fennessy, J. GiraffeThe Facts. Evol. J. Theor. Third eyelid (Plica semilunaris) Now we will try and understand the organs and their functions (if they had any) that they used to carry out before they became dormant! Over 100 million years ago, some lizards happened to be born with smaller legs, which, in certain environments, helped them move about unencumbered. The whole-genome sequence of two Masai giraffe (Giraffa camelopardalis. School of Life Sciences and Bioengineering, African Institute of Science and Technology, Arusha, 4222, Tanzania, Morris Agaba,Edson Ishengoma&Douglas R. Cavener, Biosciences Eastern and Central Africa, International Livestock Research Institute, Nairobi, GPO00100, Kenya, Department of Biology, Center for Genomics and Bioinformatics, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, 16802, Pennsylvania, USA, Morris Agaba,Webb C. Miller,Barbara C. McGrath,Chelsea N. Hudson,Oscar C. Bedoya Reina,Aakrosh Ratan,Rico Burhans,Lan Wu-Cavener,Brendan Wood&Douglas R. Cavener, Department of Physiology, MRC Functional Genomics Unit, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK, Department of Computer Science, Center for Public Health Genomics, University of Virginia, Charlottesville, 22908, Virginia, USA, Department of Computer Science and Engineering, Center for Genomics and Bioinformatics, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, 16802, Pennsylvania, USA, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, 16802, Pennsylvania, USA, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, 16802, Pennsylvania, USA, Nashville Zoo at Grassmere, Nashville, 37211, Tennessee, USA, White Oak Holdings, Yulee, 32097, Florida, USA, You can also search for this author in It is a typical example of Lamarck and giraffes: as a result of stretching the neck to reach the higher leaves of the trees, currently giraffes have this neck for giving it this use. Chromosome Res. The unique substitution in giraffe, G234Q, immediately adjacent to the Gpi anchor site may alter the anchor site or the rate of its formation. Darwin predicted them and they continue to be discovered in species all over the world. The homeobox genes HOXB3, CDX4 and NOTO exhibit enhanced divergence in giraffe among eutherians and have unique amino acid substitutions predicted to alter protein function. An anatomical structure is a body part, such as the spinal cord, in an organism. 30 seconds . Physiol. Horns, often sharp, are also used as a defense against predator attacks. That is, evolution has to be viewed as a tree, and not as a straight line, where each branch would be a species . Joberty, G. et al. All that remains are vestigial structures of the lateral ventricles, and only in rare pathological cases do humans have small air sacs (Stell and Maran 1975). The solutions to these challenges, in particular related to its turbocharged circulatory system, may be instructive for treatment of cardiovascular disease and hypertension in humans. It is what is known as natural selection, one of the main mechanisms of evolution. (b) Giraffe FOLR1 contains seven substitutions that each show evidence of positive selection (P<0.05) by the branch-site model. D.R.C. Pattern and timing of diversification of Cetartiodactyla (Mammalia, Laurasiatheria), as revealed by a comprehensive analysis of mitochondrial genomes. Nipples start to form before SRY activates, so all humans end up with nipples, regardless of their sex. 32, 17921797 (2004). Biochem. The appropriate scaffolds were analysed by the Genewise55 annotation programme using complete reference coding sequences from cattle or human. To complete the annotation for these genes, the giraffe and okapi scaffolds containing these genes were identified. Giraffe genome sequence reveals clues to its unique morphology and physiology. performed the gene annotations. 179, 481485 (1997). Structures are similar in function but not in structure. Evol. Rec. 68, 951964 (2011). Giraffes elevated stature enables it to feed on acacia leaves and seedpods that are highly nutritious but also contain toxic alkaloids. Integr. Massa, Renato. Outside the scientific field, the word theory is used to refer to events that have not been tested or assumptions. 23, 228232 (1999). Model. PANTHER: a browsable database of gene products organized by biological function, using curated protein family and subfamily classification. The Whole Genome Shotgun project of G. camelopardalis tippelskirchi (MA1) has been deposited at DDBJ/ENA/GenBank under the accession LVKQ00000000 and the version described in this paper is version LVCL01000000. Cell. <p>vestigial structures </p> answer explanation . Here we sequenced the genomes of the Masai giraffe and okapi, and through comparative analysis with other eutherians mammals, 70 genes were identified that exhibit multiple signs of adaptation (MSA) in giraffe. Mediator of DNA damage checkpoint 1 (MDC1) regulates mitotic progression. Vestigial Salmon Adipose Fin Actually Useful. (c) Genes encoding key enzymes in butyrate metabolism and downstream mitochondrial oxidative phosphorylation pathways have diverged in giraffe including the monocarboxylate transporter (MCT1), acyl-coenzyme A synthetase-3 (ACSM3), short-chain specific acyl-CoA dehydrogenase (ACADS), NADH dehydrogenase (ubiquinone) 1 subcomplex subunit 2 (NDUFB2) and succinate dehydrogenase [ubiquinone] iron-sulfur subunit (SDHB). and R.B. Giraffe ossicones are used by males during their confrontations. Vctor Quesada, Sandra Freitas-Rodrguez, Carlos Lpez-Otn, Daniel E. Chavez, Ilan Gronau, Robert K. Wayne, Feng Zhu, Zhong-Tao Yin, Zhuo-Cheng Hou, Jocelyn Plassais, Jaemin Kim, Elaine A. Ostrander, Markus Bastir, Daniel Garca-Martnez, Fred Spoor, Andrew W. Thompson, M. Brent Hawkins, Ingo Braasch, Sagar Sharad Shinde, Sandhya Sharma, Nagarjun Vijay, Nature Communications The blood vessel walls in the lower extremities are greatly thickened to withstand the increased hydrostatic pressure, and the venous and arterial systems are uniquely adapted to dampen the potentially catastrophic changes in blood pressure when giraffe quickly lowers its head to drink water1,5,6,7,8,9,10,11. Chapter 19: Unit 19, 121 (2010). 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The FOLR1 protein forms a globular structure maintained by overlapping disulfide bridges between 16 cysteine residues (red) and tethered to the plasma membrane at S233 by a Gpi anchor. Physiol. Google Scholar. 13, 24982504 (2003). The giraffe and okapi MDC1 gene contains an in-frame termination substitution in exon 5, suggesting either premature termination or alternative splicing to remove the offending termination codons. First, reads were required to have a best alignment to the reference assembly with at least 3% more identical nucleotides than the second-best alignment. Coster, G. et al. In the meantime, to ensure continued support, we are displaying the site without styles A review of vestigial structures, some of the structures in our bodies that are "leftover" from previous evolutionary phases of humanity. and B.W. Stanton, D. W. et al. J. Physiol. There are countless examples of. B. the structures are identical. A common example is that of the appendix in giraffes and also humans. 3d). E. coevolution. Correspondence to Both the evolutionist and creationist can explain vestigial eyes. . 3a) in the domain that interacts with FGF ligands. Nucleic Acids Res. It is no longer needed to break down complex cellulose in our diet like for our common ancestors. However, we found that two-thirds of the genes most diverged in giraffe have specific roles in regulating skeletal, cardiovascular and/or neural development, or physiology (Fig. The sequences that aligned to the reference genome as described above were sorted by the start position of their alignment to the reference genome. Mitchell, G. & Skinner, J. D. An allometric analysis of the giraffe cardiovascular system. B.C.M. Antlers only exist in males of the Cervidae family, except for the caribou or reindeer (Rangifer tarandus), in which both males and most of females have antlers. Vestigial structures are usually harmless though they may bring some additional weight. However, in general, females have thinner horns while in males they are wider and can withstand more force. 1). performed the gene network analysis. Two giraffe subspecies are nearly extinct and overall the number of giraffes have declined by 40% since 2000, due to poaching and habitat loss16. FGFRL1 is among nine genes in giraffe that exhibit a significantly higher number of unique amino substitutions at fixed sites in mammals (Supplementary Table 4). Rep. 2, 980 (2012). The blood pressure of giraffe is 2.5 higher than man, the left ventricle of the heart is enlarged and the blood vessel walls of the lower extremities are greatly thickened1,31. This anthropocentric thinking caused Darwin mockery and confrontations over 150 years ago. Researchers have historically considered the human appendix to be a vestigial structure. & Chen, J. MDC1 is coupled to activated CHK2 in mammalian DNA damage response pathways. Nature 421, 961966 (2003). Cell Biol. Neuroscience 148, 522534 (2007). Appendix - The Vermiform Appendix is a vestigial organ in our digestive system which was functional in our ancestors and had some digestive functions. Comparative anatomy is the study of similarities and differences in the anatomy of different species.It is closely related to evolutionary biology and phylogeny (the evolution of species).. Vestigial structures are various cells, tissues, and organs in a body which no longer serve a function. Comp. Homologous structures are structures that have a common function and suggest common ancestry. Ratan, A. Another so-called vestigial organ finds a function. Bacteria, algae, sharks, crocodiles, etc., have remained very similar over millions of years. The same paired-end and mate-pair reads that were used to assemble were mapped back to the giraffe and okapi assemblies. A vestigial structure can arise due to a mutation in the genome. Thousands of euros are paid (from 2,000 to 80,000) to make hunting safaris in Africa, for example, where the most valuable animal is the one with the largest horns. The Nextera Mate Pair Sample Preparation Kit was used to construct mate pair libraries from the same three samples using the manufacturers Gel Plus protocol with 48kb size selection. The picture below on the left shows the central ankle bones (called astragali) of three artiodactyls, and you can see they have double pulley joints and hooked processes pointing up toward the leg-bones. You are using a browser version with limited support for CSS. Over 400 genes were identified from the giraffeokapicattle analysis that exhibited some degree of genetic differentiation in giraffe by the aforementioned analysis. Bovine HapMap, C. et al. They evolve so quickly that within a few years were selected the fittest to survive our antibiotics. 335, 3250 (2012). 181, 227240 (2008). Structure A is a human arm, which is used for lifting and carrying items. Find out more in the following post. We have many evidences and in this post we will not delve into them. gial ve-sti-j-l -jl Synonyms of vestigial 1 of a body part or organ : remaining in a form that is small or imperfectly developed and not able to function : being or having the form of a vestige (see vestige sense 2) a vestigial tail Mol. J. Physiol. BORG1 and RCAN3, which are highly expressed in the heart and purported to have important functions related to cell shape and cardiac muscle contraction, respectively, are also significantly diverged in giraffe32,33. J. Linn. Camb. To determine whether substitutions unique to Masai giraffe were conserved in other giraffe subspecies, we performed targeted sequencing of several genes in Rothschild (G.c. Human reference is shown, which is identical to cattle and okapi in this segment. That's called the plica luminaris, a vestigial structure that doesn't really have a purpose but is leftover from our ancestors. 31, 334341 (2003). Chikhi, R. & Medvedev, P. Informed and automated k-mer size selection for genome assembly. A Vestigial structure is "A part of organism's anatomy that has lost all of, or most of, its original function in the course of evolution." By studying these functionless structures, we can. 94, 1117 (2009). Some of the evidence available to us are: Both expressions, frequently used, mean that living beings have an active role to adapt to the environment or someone has designed them to live exactly where they are. The human appendix helps to maintain the health of the gut, and arose fairly late in the evolutionary history of mammals. ^3 3. To pump blood vertically 2m from the heart to the brain giraffe has evolved a turbocharged heart and twofold greater blood pressure than other mammals1,5. The mappings between giraffeokapi nucleotide difference and the reference assembly allowed us to predict amino-acid difference (in the case of nonsynonymous protein-coding differences) as follows. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate. Analogous features provided the MA1 giraffe genomic DNA samples. Horns have different shapes and sizes depending on the species: straight, curved or spiral; flipped, bent or flat; short or wide. Thus, they provide strong evidence of common ancestry and can help us trace the evolutionary origin of the species with the vestigial structures. Ensembl reference transcripts with the highest degree of confidence and information (TSL:1, GENECODE basic, APPRIS P1) were used. Pressure profile and morphology of the arteries along the giraffe limb. At an older age, this protuberance is bigger, since calcium is deposited over time. Genet. Animal. Nature 421, 957961 (2003). As generation after generation survived and reproduced, this new form flourished. Authors: F. C. FRASER Abstract In the Okapi vestiges of the second and fifth metapodials may be present but they are variable in occurrence and. Do you have any questions about evolution? The pronghorn has different horns than the bovids: they are branched and the keratinized covers change annually, whereas in bovids are permanent. M.A., D.R.C., L.W.C. Article 30 coverage. Wisdom Teeth. They are made up ofa bony nucleus and an outer coating of keratin (the same protein from our hair and nails). Bulls, deer, rhinos all of them have structures on their heads that we call horns, but they are not all the same. Acta 1792, 112121 (2009). Therefore, vestigial structures can be considered evidence for evolution, the process by which beneficial heritable traits arise in population over an extended period of time. EMBO J. Giraffe and okapi genes are highly similar overall with 19.4% of proteins being identical (Fig. . It is a body structure that can include internal organs, tissues and organ systems. Nature 427, 419422 (2004). C.H. Traits that have arisen as a result of common evolutionary descent are said to be . Summary: As shown in the evolutionary tree (Picture C), giraffes and okapis evolved from a common ancestor, the pre-okapi. Are all horns the same? Neck of Giraffe is an example of which concept ? Bioinformatics 25, 20782079 (2009). In addition, several identified genes functionally intersect metabolism, growth and cardiovascular function, suggesting that giraffes unique features may have co-evolved to elevate its stature, adapt its metabolism for more toxic food sources and adapt its cardiovascular and nervous system to the increased demands imposed by its unique morphology. J. Biol. Vestigial Structures Explained In addition, the horn is placed above the nasal bones, not in frontal position as in the case of antlers and true horns. Scaffolds were assembled using SOAPdenovo2 (v2.04)57, setting k-mer size to 91 for the giraffe data set and 81 for the okapi data set, and enabling repeat resolution (-R parameter). This number, when combined with the similar structure of the human and giraffe spine, allows the scientific community to posit that humans and giraffes, as different as they may be, share a common ancestor. Theory of Evolution has various consequences, such as the existence of a common ancestor and that therefore, that we are animals. By submitting a comment you agree to abide by our Terms and Community Guidelines. These vestigial hindlimbs are evidence of basilosaurids' terrestrial heritage. have gotten rid of all their vestigial structures. Included among the MSA genes in giraffe are those involved in the catabolism of volatile fatty acids such as butyrate (MCT1, ACSM3 and ACADS) or downstream oxidative phosphorylation that generate ATP (NDUB2 and SDHB) (Fig. Mice lacking the folic acid-binding protein Folbp1 are defective in early embryonic development. PPT. Dimitrova, N. & de Lange, T. MDC1 accelerates nonhomologous end-joining of dysfunctional telomeres. Perhaps, not surprisingly, the amino acid sequence of NIBRIN, MRE11 and SOSB2, and BAZB1, which interact with MDC1 (ref. 21, 447460 (2013). Vestigial structures are fascinating. Hum. In females, the horn would help to protect the young, whereas in males to face their rivals. The complementary DNAs from both giraffe and okapi liver tissue were truncated in exon 5, indicating the use of a cryptic 5-splice site resulting in a 264-amino acid internal deletion not seen in any other vertebrate. Vestigial structure is used in. Susaeta. Vestigial features of humans and other organisms are well known and have long been used as key evidence for evolution. Vestigiality describes homologous characters of organisms which have lost all or most of their original function in a species through evolution. Science 324, 528532 (2009). Gigascience 2, 17 (2013). Sensorimotor responsiveness and resolution in the giraffe. Ed. Seventy genes displayed MSA in giraffe by these criteria (Supplementary Table 4 and Supplementary Fig. Ed. coordinated the project, performed enhanced gene annotations, performed the dN/dS screen and pathway enrichment analyses, and identified and collated the set of MSA genes. and JavaScript. Therefore, living beings are mere spectators of the evolutionary process, dependingof changes in their habitat and their genetic material. M.A. Nat. answer choices . . Rhinos have small eyes and fairly short but prominent and erect ears. 20, 32383243 (2006). It is noteworthy that the percentage of properly mapping mate pairs was lower than for paired ends, as the larger span of a mate pair makes it more likely to map across different scaffolds. Giraffes necks have seven cervical vertebrae, and together they are approximately eight feet in length and weigh over 600 pounds. We can survive without it. 1. Soc. The more harmful the vestigial structures, the faster it takes to phase them out. M.A. Mol. P48S is within -sheet-1 that forms part of the folic acid-binding pocket. 76, 217224 (1983). Sci. CAS These are structures that have been reduced to the point that they are virtually useless. and E.I. and D.R.C. These organs are allegedly left over from our ancestors but are no longer useful or needed. The sheep genome illuminates biology of the rumen and lipid metabolism. The only exceptions are the manatee and . We thank the Kenya Wildlife Service for providing the giraffe tissue from the MA1. B.C.M. Biol. All bovids (bulls, goats, sheep, antelopes) have horns, including the females in many species. FGFRL1 is known to be essential for normal skeletal and cardiovascular development in humans and mice25,26,27, and the FGF pathway regulates somite size51. Okapi, which lacks these unique features, is giraffes closest relative and provides a useful comparison, to identify genetic variation underlying giraffes long neck and cardiovascular system. Ear muscles and the tail bones are examples of vestigial structures in our own species. Evol. Biol. Townsend, K. et al. Galaxy tools to study genome diversity. Anat. Q. Biology of FGFRL1, the fifth fibroblast growth factor receptor. Bootstrapping (n=100) was used to test the robustness of the resulting phylogenies. A. Rhinos have a broad chest and short, stumpy legs. 1999. Fossils: This PowerPoint on The Fossil Record is geared to any Middle or High School Science or Biology class/grade. 60), using likelihood ratio tests (LRTs). Photos: A-E, Steve Demarais, F, Dave Hewitt. Yang, Z. PAML 4: phylogenetic analysis by maximum likelihood. wrote the paper. Regul. structures in taxa for which, to our knowledge, vestigial structures had not been previously documented, we examined more than one specimen per species when possible ( T able 1 ). Giraffes unique anatomy imposes considerable existential challenges and three systems bear the greatest burden: the cardiovascular system to maintain blood pressure homeostasis1, the musculoskeletal system to support a vertically elongated body mass2 and the nervous system to rapidly relay signalling over long neural networks3,4. Circulation 104, 729734 (2001). Vestigial StructureA vestigial structure is a structure that appears to no longer have a use in the body. 14, 219 (2014). Another example is that of cave-dwelling tetra fish. Report an issue . To test for signatures of positive selection acting on giraffe lineage for each of the genes, we compared the likelihood scores of selection models implemented in CODEML in the PAML package, version 4.7 (ref. Cite this article. Accuracy and power of bayes prediction of amino acid sites under positive selection.
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