Dromaiidae

Dromaiidae
  • 文章类型: Journal Article
    the是日本的一种新型家禽。然而,由于近亲繁殖,日本养殖的e种群减少了遗传多样性。我们以前曾建议,东北野生动物园(TSP)和富士/川川Kachoen花园公园(FGP/KGP)中存在遗传资源,以基于微卫星(SSR)和线粒体DNA扩展商业emu农场的遗传多样性。然而,这些标记提供的信息相对较差。因此,我们基于使用RAD-seq的大规模基因分型系统调查了日本养殖种群的遗传结构,并验证了TSP和FGP/KGP作为遗传资源对扩大遗传多样性的有用性。外加剂,系统发育,基于28,676个SNP的主成分分析表明,TSP个体是鄂霍次克Emu农场(OEF)的祖先。FGP/KGP个体表现出与其他个体不同的独特遗传成分。我们以前曾报道过,FGP/KGP的线粒体单倍型与澳大利亚东部的一个孤立的野生种群共享。这些结果表明,FGP/KGP个体起源于澳大利亚东部的孤立种群,与包括OEF/TSP祖先在内的其他种群不同。我们的结果将为日本emu农场和工业的发展以及澳大利亚野生emu的遗传资源保护提供信息。
    The emu is a novel poultry species in Japan. However, Japanese farmed emu populations have reduced genetic diversity owing to inbreeding. We have previously suggested that there are genetic resources in the Tohoku Safari Park (TSP) and Fuji/Kakegawa Kachoen Garden Park (FGP/KGP) to extend the genetic diversity of commercial emu farms based on microsatellite (SSR) and mitochondrial DNA. However, those markers provide relatively poor information. Thus, we investigated the genetic structure of farmed Japanese populations based on a large-scale genotyping system using RAD-seq and verified the usefulness of TSP and FGP/KGP as genetic resources for expanding genetic diversity. Admixture, phylogenetic, and principal component analyses based on 28,676 SNPs showed that TSP individuals were ancestors in the Okhotsk Emu Farm (OEF). FGP/KGP individuals showed a unique genetic component that differed from that of the others. We have previously reported that the mitochondrial haplotypes of FGP/KGP were shared with an isolated wild population in eastern Australia. These results suggest that FGP/KGP individuals originated from an eastern Australia isolated population different from other populations including ancestral of OEF/TSP. Our results would provide information for the development of Japanese emu farms and industry and for the conservation of genetic resources in the Australian wild emu.
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  • 文章类型: Journal Article
    16SrRNA靶向扩增子测序是阐明微生物群落组成的既定标准。虽然高通量短读取测序由于其有限的读取长度而只能引发一部分16SrRNA基因,第三代测序可以完整读取16SrRNA基因,从而提供更精确的分类学分类。这里,我们提出了使用牛津纳米孔技术(ONT)生成全长16SrRNA序列的协议,以及使用Emu的微生物群落概况。我们选择Emu来分析ONT序列,因为它利用来自整个社区的信息来克服由于不完整的参考数据库和硬件限制而导致的错误,最终获得物种级别的分辨率。该管道提供了一种低成本的解决方案,通过利用实时,长读取ONT测序和定制的软件,用于准确表征微生物群落。©2024Wiley期刊有限责任公司。基本方案:使用Emu进行微生物群落分析支持方案1:使用OxfordNanoporeTechnologies测序平台进行全长16SrRNA微生物序列支持方案2:为Emu建立自定义参考数据库。
    16S rRNA targeted amplicon sequencing is an established standard for elucidating microbial community composition. While high-throughput short-read sequencing can elicit only a portion of the 16S rRNA gene due to their limited read length, third generation sequencing can read the 16S rRNA gene in its entirety and thus provide more precise taxonomic classification. Here, we present a protocol for generating full-length 16S rRNA sequences with Oxford Nanopore Technologies (ONT) and a microbial community profile with Emu. We select Emu for analyzing ONT sequences as it leverages information from the entire community to overcome errors due to incomplete reference databases and hardware limitations to ultimately obtain species-level resolution. This pipeline provides a low-cost solution for characterizing microbiome composition by exploiting real-time, long-read ONT sequencing and tailored software for accurate characterization of microbial communities. © 2024 Wiley Periodicals LLC. Basic Protocol: Microbial community profiling with Emu Support Protocol 1: Full-length 16S rRNA microbial sequences with Oxford Nanopore Technologies sequencing platform Support Protocol 2: Building a custom reference database for Emu.
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  • 文章类型: Journal Article
    在不同的牵引条件下,齿轮传动系统的振动和辐射噪声特性不同,基于单一工况的齿轮修形优化方案不适合所有工况下的作业环境。要改装高速动车组的牵引齿轮,提出了一种多工况下降噪的优化设计方案。使用动车组牵引齿轮传动系统的参数化模型,设计了齿向与齿形相结合的修正方案。在不同工况下,采用声边界元法求解了改型后齿轮传动系统的辐射噪声。提出了一种基于随机森林的齿轮噪声预测模型,并构造了齿轮修正参数组合,以最大程度地降低辐射噪声。然后,以不同工况下的运行时间和声学贡献为权重,得到了多工况修正组合参数的优化设计方案。建立灰色关联度评价模型,验证了多工况修正优化设计方法能够使动车组牵引齿轮在不同工况下获得满意的传动性能和降噪效果。
    The vibration and radiation noise characteristics of the gear transmission system are different under different traction conditions, and the gear modification optimization scheme based on a single working condition is not suitable for the operating environment under all working conditions. To modify the traction gear of a high-speed EMU, an optimized design scheme for noise reduction under multiple working conditions is proposed. A modification plan of the tooth direction in conjunction with the tooth shape was devised using a parametric model of the EMU\'s traction gear transmission system. The radiation noise of the gear transmission system after modification was solved using the acoustic boundary element method under different working conditions. A gear noise prediction model based on the random forest was proposed, and a gear modification parameter combination was constructed to minimize radiation noise. Then, the optimal design scheme of multi-condition modification combination parameters is obtained with the weight of the running time and acoustic contribution under different working conditions. The grey correlation degree evaluation model is established to verify that the multi-condition modification optimization design method can make the traction gear of EMU obtain satisfactory transmission performance and noise reduction effect under different working conditions.
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  • 文章类型: Journal Article
    Emus(Dromaiusnovaehollandiae),一个巨大的不会飞的杂食性平胸,是为了他们的脂肪和肉而养殖的。emu脂肪可以制成油用于治疗和美容用途。它们能够从植物纤维的消化中获得其日常能量需求的很大一部分。尽管它体型大,代谢率低,emus具有相对简单的胃肠(GI)道,平均消化保留时间短。然而,对emus的GI微生物多样性知之甚少。本研究的目的是表征小肠不同节段(十二指肠,空肠,和回肠)使用pyrotag测序并将其与盲肠进行比较。从四个成年emus(2个雄性,2名女性;5-6岁),自由放养,但补充了基于大麦-苜蓿-油菜的饮食。我们使用Roche454Junior系统扩增了16SrRNA基因的V3-V5区域以鉴定细菌群落。质量修整后,从小肠(SI)的不同区段获得总共165,585个序列读数。在小肠的不同部分中总共鉴定出701个操作分类单位(OTU)。厚壁菌(14-99%)和变形杆菌(0.5-76%)是小肠中最主要的细菌门。基于物种丰富度估计(Chao1指数),十二指肠小肠隔室中估计的OTU的平均数量为148,167在空肠,85在回肠,分别。在单个鸟类的小肠的每个隔室中识别出的核心OTU数量较少(十二指肠:13个OTU,空肠:2个OTU,回肠:14个OTU)表明每只鸟中独特的细菌群落。此外,在整个小肠中,只有2个OTUs(埃希氏菌和中细菌科)被鉴定为核心细菌。PICRUSt分析表明,植物材料和环境化学物质的解毒似乎是由SI微生物群进行的,尤其是空肠里的.emu盲肠微生物组比SI片段具有更多的基因,涉及对肠道病原体的保护性或免疫反应。微生物消化和发酵大多在空肠和盲肠。这是第一项通过肠道样品而不是粪便样品表征the肠不同区室微生物群的研究。这项研究的结果使我们能够进一步研究肠道菌群的季节性和生理变化对emus营养的影响,并间接影响emu脂肪的脂肪酸组成。
    Emus (Dromaius novaehollandiae), a large flightless omnivorous ratite, are farmed for their fat and meat. Emu fat can be rendered into oil for therapeutic and cosmetic use. They are capable of gaining a significant portion of its daily energy requirement from the digestion of plant fibre. Despite of its large body size and low metabolic rate, emus have a relatively simple gastroinstetinal (GI) tract with a short mean digesta retention time. However, little is known about the GI microbial diversity of emus. The objective of this study was to characterize the intraluminal intestinal bacterial community in the different segments of small intestine (duodenum, jejunum, and ileum) using pyrotag sequencing and compare that with the ceca. Gut content samples were collected from each of four adult emus (2 males, 2 females; 5-6 years old) that were free ranged but supplemented with a barley-alfalfa-canola based diet. We amplified the V3-V5 region of 16S rRNA gene to identify the bacterial community using Roche 454 Junior system. After quality trimming, a total of 165,585 sequence reads were obtained from different segments of the small intestine (SI). A total of 701 operational taxonomic units (OTUs) were identified in the different segments of small intestine. Firmicutes (14-99%) and Proteobacteria (0.5-76%) were the most predominant bacterial phyla in the small intestine. Based on species richness estimation (Chao1 index), the average number of estimated OTUs in the small intestinal compartments were 148 in Duodenum, 167 in Jejunum, and 85 in Ileum, respectively. Low number of core OTUs identified in each compartment of small intestine across individual birds (Duodenum: 13 OTUs, Jejunum: 2 OTUs, Ileum: 14 OTUs) indicated unique bacterial community in each bird. Moreover, only 2 OTUs (Escherichia and Sinobacteraceae) were identified as core bacteria along the whole small intestine. PICRUSt analysis has indicated that the detoxification of plant material and environmental chemicals seem to be performed by SI microbiota, especially those in the jejunum. The emu cecal microbiome has more genes than SI segments involving in protective or immune response to enteric pathogens. Microbial digestion and fermentation is mostly in the jejunum and ceca. This is the first study to characterize the microbiota of different compartments of the emu intestines via gut samples and not fecal samples. Results from this study allow us to further investigate the influence of the seasonal and physiological changes of intestinal microbiota on the nutrition of emus and indirectly influence the fatty acid composition of emu fat.
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  • 文章类型: Journal Article
    基于16S核糖体RNA的分析是阐明微生物群落组成的既定标准。虽然短读16SrRNA分析在很大程度上仅限于属级别的分辨率,鉴于只有一部分基因被测序,全长16SrRNA基因扩增子序列具有提供物种水平准确性的潜力。然而,现有的分类识别算法没有针对长读取数据中经常观察到的增加的读取长度和错误率进行优化。在这里,我们介绍Emu,一种使用期望最大化算法从全长16SrRNA读数生成分类丰度谱的方法。从模拟数据集和模拟社区产生的结果表明,与其他方法相比,Emu能够进行准确的微生物群落分析,同时获得更少的假阳性和假阴性。此外,我们通过比较由已建立的全基因组鸟枪测序工作流程产生的临床样本组成估计值与由Emu处理的全长16SrRNA基因序列返回的样本组成估计值,说明了Emu的实际应用.
    16S ribosomal RNA-based analysis is the established standard for elucidating the composition of microbial communities. While short-read 16S rRNA analyses are largely confined to genus-level resolution at best, given that only a portion of the gene is sequenced, full-length 16S rRNA gene amplicon sequences have the potential to provide species-level accuracy. However, existing taxonomic identification algorithms are not optimized for the increased read length and error rate often observed in long-read data. Here we present Emu, an approach that uses an expectation-maximization algorithm to generate taxonomic abundance profiles from full-length 16S rRNA reads. Results produced from simulated datasets and mock communities show that Emu is capable of accurate microbial community profiling while obtaining fewer false positives and false negatives than alternative methods. Additionally, we illustrate a real-world application of Emu by comparing clinical sample composition estimates generated by an established whole-genome shotgun sequencing workflow with those returned by full-length 16S rRNA gene sequences processed with Emu.
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  • 文章类型: Journal Article
    Emus被养殖用于生产脂肪。从背部和腹部脂肪垫提供的油具有良好的抗氧化和抗炎特性,并具有促进细胞生长的成分。我们的目标是检查7种emu脂肪因子基因的mRNA表达(eFABP4,eSCD1,eAdipoQ,eAdipoR1,eAdipoR2,eLEP和eLepR)以鉴定可能有助于改善emu脂肪产生的基因标记。在四个时间点对11例成年动脑的背部和腹部脂肪组织进行活检(4月,六月,8月和11月)。分离总RNA并合成cDNA。设计基因特异性引物用于部分克隆片段,扩增7个基因的开放阅读框。eLEP在emu脂肪组织中不表达。将6个表达基因的核苷酸和氨基酸序列与其他物种的同源物进行比较,并建立了系统发育关系。通过定量RT-PCR评估每个基因的季节性mRNA表达,并通过2-ΔΔCT方法分析差异表达。6个表达基因的表达呈季节性变化,表达水平与背部脂肪肥胖有关。需要更多的全基因组扫描研究来开发新的分子标记,这些标记可以用于改善动脑中的脂肪产生。
    Emus are farmed for fat production. Oil rendered from their back and abdominal fat pads has good anti-oxidant and anti-inflammatory properties and has ingredients that promote cell growth. Our objective is to examine the mRNA expression of 7 emu adipokine genes (eFABP4, eSCD1, eAdipoQ, eAdipoR1, eAdipoR2, eLEP and eLepR) to identify gene markers that may help improve emu fat production. Back and abdominal fat tissues from 11 adult emus were biopsied at four time points (April, June, August and November). Total RNA was isolated and cDNA was synthesized. Gene specific primers were designed for partial cloning fragments to amplify the open reading frame of the 7 genes. eLEP was not expressed in emu fat tissue. Nucleotides and amino acids sequences of the 6 expressed gene were compared with homologs from other species and phylogenetic relationships established. Seasonal mRNA expression of each gene was assessed by quantitative RT-PCR and differential expression analysed by the 2-ΔΔCT method. The 6 expressed genes showed seasonal variation in expression and showed association of expression level with back fat adiposity. More whole-genome scanning studies are needed to develop novel molecular markers that can be applied to improve fat production in emus.
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  • 文章类型: Journal Article
    鸵鸟和em是现存最大的鸟类之一,经常被用作非禽类兽脚类恐龙生长动态的现代类似物。这些平脱物在不到一年的时间内迅速达到成人大小,因此通常不会表现出每年沉积的生长标记。成长标记,通常归类为环状物或生长停滞线(LAG),代表骨生成减少或停止,分别,它们的存在证明了不同程度的发育可塑性。鸵鸟和emus尚未报告生长标记,促使作者建议他们已经失去了沉积它们所需的可塑性。在这里,我们观察了三个圈养的幼年emus和一个圈养的成年鸵鸟的后肢骨组织学。三个少年emu中的两个表现出典型的骨组织,但第三个emu,一个4.5个月大的少年,表现出无血管组织的区域弧,我们将其解释为增长标记。由于该标记不存在于同一队列的其他两个emus中,并且与对侧腓骨骨折同时出现,我们建议可变的生物力学负荷是一个潜在的原因。鸵鸟展示了一个完整的无血管环,高矿化骨稀疏,扁平的骨细胞腔隙。我们认为这是一个环,并将其解释为增长放缓。在没有其他生长标记和缺乏动物的生活史的情况下,这只鸵鸟生长减少的时间和原因尚不清楚。即便如此,这些发现表明,两个类群都保留了暂时减缓生长所需的祖先发育可塑性。我们还讨论了使用不完整的种群数据集和部分皮层采样来识别生长标记的潜在挑战。
    Ostriches and emus are among the largest extant birds and are frequently used as modern analogs for the growth dynamics of non-avian theropod dinosaurs. These ratites quickly reach adult size in under 1 year, and as such do not typically exhibit annually deposited growth marks. Growth marks, commonly classified as annuli or lines of arrested growth (LAGs), represent reduced or halted osteogenesis, respectively, and their presence demonstrates varying degrees of developmental plasticity. Growth marks have not yet been reported from ostriches and emus, prompting authors to suggest that they have lost the plasticity required to deposit them. Here we observe the hind limb bone histology of three captive juvenile emus and one captive adult ostrich. Two of the three juvenile emus exhibit typical bone histology but the third emu, a 4.5-month-old juvenile, exhibits a regional arc of avascular tissue, which we interpret as a growth mark. As this mark is not present in the other two emus from the same cohort and it co-occurs with a contralateral broken fibula, we suggest variable biomechanical load as a potential cause. The ostrich exhibits a complete ring of avascular, hypermineralized bone with sparse, flattened osteocyte lacunae. We identify this as an annulus and interpret it as slowing of growth. In the absence of other growth marks and lacking the animal\'s life history, the timing and cause of this ostrich\'s reduced growth are unclear. Even so, these findings demonstrate that both taxa retain the ancestral developmental plasticity required to temporarily slow growth. We also discuss the potential challenges of identifying growth marks using incomplete population data sets and partial cortical sampling.
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  • 文章类型: Journal Article
    慢性淋巴细胞白血病(CLL)是由成熟的CD5B细胞在次级淋巴器官中的进行性积累引起的。体外数据表明CD4+T淋巴细胞也通过CD40L/CD40相互作用维持CLL克隆的存活和增殖。动物模型中的体内数据是相互矛盾的。为了澄清这个临床相关的生物学问题,我们产生了缺乏CD4+T细胞的转基因Eμ-TCL1小鼠(TCL1+/+AB0),CD40(TCL1+/+CD40-/-),或CD8+T细胞(TCL1+/+TAP-/-),我们通过流式细胞术和免疫组织化学分析监测了一种模拟侵袭性人类CLL的疾病的出现和进展。通过将白血病细胞过继性转移到缺乏CD4T细胞或CD40L的小鼠或用抗体清除CD4T细胞或阻断CD40L/CD40相互作用的小鼠中证实了这一发现。CLL克隆在缺乏或耗尽CD4+T细胞的小鼠中不增殖,从而证实CD4+T细胞是CLL发育所必需的。相比之下,CD8+T细胞发挥抗肿瘤活性,如TCL1+/+TAP-/-小鼠中加速的疾病进展所示。CD4+T细胞的抗原特异性是CLL发展的边缘,因为CLL克隆在转基因小鼠中有效增殖,其CD4T细胞具有具有CLL无关特异性的T细胞受体。当转移到用阻断CD40的单克隆抗体治疗的野生型小鼠或CD40L-/-小鼠中时,白血病克隆也会增殖,和TCL1+/+CD40-/-小鼠出现FrankCLL。我们的数据表明,CD8+T细胞抑制CLL进展,而CD4+T细胞通过CD40非依赖性和明显的非同源机制支持TCL1小鼠中白血病克隆的生长。
    Chronic lymphocytic leukemia (CLL) is caused by the progressive accumulation of mature CD5+ B cells in secondary lymphoid organs. In vitro data suggest that CD4+ T lymphocytes also sustain survival and proliferation of CLL clones through CD40L/CD40 interactions. In vivo data in animal models are conflicting. To clarify this clinically relevant biological issue, we generated genetically modified Eμ-TCL1 mice lacking CD4+ T cells (TCL1+/+AB0), CD40 (TCL1+/+CD40-/-), or CD8+ T cells (TCL1+/+TAP-/-), and we monitored the appearance and progression of a disease that mimics aggressive human CLL by flow cytometry and immunohistochemical analyses. Findings were confirmed by adoptive transfer of leukemic cells into mice lacking CD4+ T cells or CD40L or mice treated with antibodies depleting CD4 T cells or blocking CD40L/CD40 interactions. CLL clones did not proliferate in mice lacking or depleted of CD4+ T cells, thus confirming that CD4+ T cells are essential for CLL development. By contrast, CD8+ T cells exerted an antitumor activity, as indicated by the accelerated disease progression in TCL1+/+TAP-/- mice. Antigen specificity of CD4+ T cells was marginal for CLL development, because CLL clones efficiently proliferated in transgenic mice whose CD4 T cells had a T-cell receptor with CLL-unrelated specificities. Leukemic clones also proliferated when transferred into wild-type mice treated with monoclonal antibodies blocking CD40 or into CD40L-/- mice, and TCL1+/+CD40-/- mice developed frank CLL. Our data demonstrate that CD8+ T cells restrain CLL progression, whereas CD4+ T cells support the growth of leukemic clones in TCL1 mice through CD40-independent and apparently noncognate mechanisms.
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  • 文章类型: Journal Article
    现有文献缺乏有关循环停止后e肌发生的代谢过程的信息。因此,这项研究是为了检查物理化学特性(pH,滴水损失,WHC,TBARS,L*,a*,b*)伴随着股骨肌肉(M.的蛋白质表达模式(SDS-PAGE)的变化髂外侧肌)发生在死后和最初几天(0小时,24h,48小时)在1岁和3岁的emus中成熟。我们的结果表明,emus年龄和储存时间之间的相互作用对肉的pH和所有颜色指标有显着影响。此外,我们检测到24个差异表达的蛋白带,代表22种不同的基因产物。ClueGO通路分析显示这些蛋白主要参与糖酵解/糖异生途径,丙酮酸代谢和焦磷酸水解驱动的质子跨膜转运蛋白活性。根据获得的结果,可以假设,the肌的死后早期代谢主要基于糖酵解,如糖原分解和糖酵解酶的相对丰度变化所反映的。此外,ATP和其他高能物质降解提供的能量供应在老年emus组中较高。我们的发现还强调了肌肉转化为肉类的分子机制的复杂性。
    The available literature lacks information on the metabolic processes taking place in emu muscles after the cessation of circulation. Hence, this study was undertaken to examine the physicochemical characteristics (pH, drip loss, WHC, TBARS, L*, a*, b*) with concomitant changes in protein expression patterns (SDS-PAGE) of femoral muscle (M. iliotibialis lateralis) that occur post mortem and during the first days (0 h, 24 h, 48 h) of its maturation in 1- and 3-year-old emus. Our results indicated that the interaction between emus age and storage time had significant impact on meat pH and all color indicators. Furthermore, we detected 24 differentially expressed protein bands, representing 22 different gene products. ClueGO pathways analysis revealed that these proteins were mainly involved in glycolysis/gluconeogenesis pathway, pyruvate metabolism and pyrophosphate hydrolysis-driven proton transmembrane transporter activity. Based on the results obtained it can be assumed that early post-mortem metabolism of emu muscle is predominantly based on the glycolysis as reflected by the relative abundance alterations of the glycogenolytic and glycolytic enzymes. Moreover, the energy supplies provided by ATP and other high-energy substances degradation is higher in the group of older emus. Our findings also highlighted the complexity of the molecular mechanisms underlying the conversion of muscle to meat.
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  • 文章类型: Journal Article
    澳大利亚南部的岛屿曾经拥有大陆e的三个亚种(Dromaiusnovaehollandiae),较小的塔斯马尼亚emu(D.n.diemenensis)和两个矮生em,国王岛emu(D.n.小调)和袋鼠岛emu(D.n.baudinianus),所有这些在人类定居者发现后迅速灭绝。他们的生活史记录很少,只有少数历史博物馆标本存在,包括塔斯马尼亚岛的许多完整鸡蛋和袋鼠岛的独特鸡蛋。这里,我们对侏儒的卵进行了详细的分析,包括来自国王岛的几乎完整的标本的第一记录。我们的结果表明,尽管所有岛屿的尺寸都减少了,尤其是国王岛emu,平均比大陆鸟类小44%,鸡蛋在线性测量中保持相似的大小,但体积和质量较小,看起来蛋壳有点薄。我们提供了这些现象发生的可能原因。
    Islands off southern Australia once harboured three subspecies of the mainland emu (Dromaius novaehollandiae), the smaller Tasmanian emu (D. n. diemenensis) and two dwarf emus, King Island emu (D. n. minor) and Kangaroo Island emu (D. n. baudinianus), which all became extinct rapidly after discovery by human settlers. Little was recorded about their life histories and only a few historical museum specimens exist, including a number of complete eggs from Tasmania and a unique egg from Kangaroo Island. Here, we present a detailed analysis of eggs of dwarf emus, including the first record of an almost complete specimen from King Island. Our results show that despite the reduction in size of all island emus, especially the King Island emu that averaged 44% smaller than mainland birds, the egg remained similar sized in linear measurements, but less in volume and mass, and seemingly had a slightly thinner eggshell. We provide possible reasons why these phenomena occurred.
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