Age and size structure of populations of small marbled newts (Triturus marmoratus pygmaeus) from Doñana National Park (SW Spain). A case of dwarfism among dwarfs

The body size of specimens of Triturus marmoratus pygmaeus from Doñana is the smallest recorded for this subspecies. Snout-vent length averages 42.3 mm in males, and 43.9 mm in females. Mean body mass in males is 2.04 g and 2.29 g in females. The age of newts was estimated by means of skeletochronological methods. The maximum longevity recorded was 10 years in females and nine years in males, with one or two years being the age at maturity. As in other newts, body size is not a good predictor of age, since a wide range of body length was found within each age class. Growth in females was substantial in subsequent years, showing an overall positive tendency. However, males showed slight or even negative growth. Newts from Doñana are different from other nearby localities with similar climatic characteristics. This is mainly due to their short juvenile and terrestrial phase.     

乐山棒花鱼形态特征的两性异形和雌性个体生育力

测定了乐山棒花鱼(Abbottina kiatingensis)繁殖期形态特征包括体长、头长、头宽、头高、吻长、眼后头长、眼径、眼间距、体高、尾柄长、尾柄高、尾鳍长、背鳍基前距、背鳍基长、腹鳍基前距、腹臀间距、体重和去内脏体重的两性异形和雌性个体生育力。繁殖期雄性个体的数量显著多于雌性个体,雌雄两性个体的体长差异不显著。特定体长的雌性个体的头长、头宽、头高、吻长、眼后头长、尾柄高、背鳍基前距、背鳍基长和去内脏体重显著小于雄性个体,其余指标不存在明显的差异。回归分析表明,乐山棒花鱼的怀卵数量与体长和体重回归关系显著,雌性通过个体大小(体长和体重)的增加来提高个体生育力。     

棒花鱼形态特征的两性异形和雌性个体生育力

测定了棒花鱼(Abbottina rivularis)繁殖期形态特征包括体长、头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、胸鳍腹鳍间距、尾柄长、尾鳍长和体重的两性异形和雌性个体生育力。结果表明,雄性个体的数量显著多于雌性个体,雄性个体的体长显著大于雌性个体。特定体长的雌性个体的胸鳍腹鳍间距显著大于雄性个体,头长、头宽、头高、眼间距、鼻间距、背鳍基长、胸鳍长、尾柄长和尾鳍长显著小于雄性个体,雌雄两性体重不存在显著差异。棒花鱼的怀卵数量与体长和体重回归关系显著。偏相关分析显示,当控制第三者恒定时,怀卵数量与体长和体重呈正相关但不显著。棒花鱼存在个体大小和其他局部特征显著的两性异形,雌性个体主要通过腹腔容积的增加提高个体生育力。棒花鱼形态特征的两性异形是性选择和生育力选择共同作用的结果。     

皮纹密度的初步研究

本文对ab、ad、td、Δatd四种皮纹密度进行了初步分析与研究,结果表明,四种皮纹密度有明显的年龄差异,其性别差异随年龄增大而明显,左右手差异随年龄的增大而减弱。四种皮纹密度与七项测量性特征呈不同程度与性质的相关。     

Body size variation in <Emphasis Type="Italic">Gryon gallardoi</Emphasis> related to age and size of the host

This study aimed to evaluate the influence of Spartocera dentiventris (Berg) (Hemiptera: Coreidae) egg quality (regarding age, size and superparasitism) on male and female body size of Gryon gallardoi Brèthes (Hymenoptera: Scelionidae). It was also analysed host size influence on offspring sex choice and female oviposition order (within egg groups). Groups of 12 eggs, 2, 3, 4, 5, 6, 7, 8, and 12 days old were individually exposed to a female parasitoid for 2 h, and the order of each egg parasitisation was recorded. Size of adult parasitoids (head width and tibia length of the second leg pair), and parasitised and superparasitised host eggs were measured. Sexual dimorphism related to size (SDs), was estimated through a model II linear regression. Females have a larger head width but a smaller tibia length. Parasitoid adult size is significantly related to host age and size. Within an egg group, females did not exhibit preference for any egg size category either to start oviposition or to oviposit male or female eggs. The body size of both sexes diminished with host aging. There was a positive response in both sexes to host size increasing. Estimated SDs diminished with host aging and increased with host volume augmentation. The results suggest that adult body size of G. gallardoi, as well as size differences between males and females, are strongly associated to host quality.     

Sex Ratio and Sexual Size Dimorphism in a Toad-headed Lizard,Phrynocephalus guinanensis

Phrynocephalus guinanensis has sexual dimorphism in abdominal coloration, but its ontogenetic development of sexual size dimorphism(SSD) is unknown. Using mark-recapture data during four days each year from August from 2014 to 2016, we investigated the development of sex ratios, SSD, sex-specific survivorship and growth rates in a population of P. guinanensis. Our results indicated that the sex ratio of males to females was 1:2.8. Males had a lower survival rate(6%) than females(14%) across the age range from hatchling to adult, which supported the discovered female-biased sex ratio potentially associated with the low survival rate of males between hatchlings and juveniles. Male-biased SSD in tail length and head width existed in adults rather than in hatchling or juvenile lizards. The growth rates in body dimensions were undistinguishable between the sexes during the age from hatchling to juvenile, but the growth rate in head length from juvenile to adult was significantly larger in males than females. Average growth rate of all morphological measurements from hatchling to juvenile were larger compared with corresponding measurements from juvenile to adult, but only being significant in tail length, head width, abdomen length in females and snout-vent length in males. We provided a case study to strengthen our understanding of the important life history traits on how a viviparous lizard population can survive and develop their morphology in cold climates.     

黄颡鱼的两性异形和雌性繁殖特征

测定了黄颡鱼成体的体长、头长、头宽、头高、吻长、眼径、眼间距、眼后头长、体高、尾柄高、背鳍基前距、背鳍基长、尾柄长、腹鳍基前距、背鳍脂鳍间距、腹鳍臀鳍间距、尾鳍长、体重、去内脏体重等形态指标以及雌体的怀卵数量。雌性成体的体长显著小于雄性成体。其它局部特征皆与体长呈正相关,回归剩余值的t—检验表明,雌性成体的眼径、头高、体高、腹鳍基前距、体重显著大于雄性成体,其它局部形态特征不存在显著的两性差异。黄颡鱼雌体通过个体大小的增加和腹部形态的改变增加腹腔容量,增加繁殖输出。     

Comparative effects of angiotensin II on osmotic water permeability in the toad (Bufo arenarum)

The possible relationship between the renin-angiotensin system and water balance in the toad Bufo arenarum has been indirectly explored. A positive correlation was found between the hydrosmotic response of ventral pelvic toad skin to angiotensin II (A II) and some age indicators (body weight, snout-urostyle length or head width). A different hydrosmotic response for oxytocin and isoproterenol (but not for A II) was found between four cutaneous regions of toad body. We conclude that A II may not be directly involved in the regulation of water balance mediated by water absorption across the skin of Bufo arenarum toads.     

The evolution of the adult body form of the crested newt (Triturus cristatus superspecies,Caudata, Salamandridae)

We characterized the adult body form of the crested newt (Triturus cristatus superspecies) and explored its evolution. From seven morphometric traits, we determined that body size, interlimb distance and head width define the body form. None of the morphometric traits showed a phylogenetic signal. Three body‐shape morphotypes (Triturus dobrogicus + T. cristatus, Triturus carnifex + Triturus macedonicus and Triturus karelinii + Triturus arntzeni) and three body‐size morphotypes (T. dobrogicus, T. cristatus and all other crested newts) could be recognized. The ancestral phenotype (a large body with a short trunk and a wide head) characterized T. karelinii and T. arntzeni. Triturus carnifex and T. macedonicus had a somewhat different phenotype (large body and wide head, accompanied by mild body elongation). The most derived phenotype included body size reduction and more pronounced body elongation in T. cristatus and, especially, in T. dobrogicus. Body elongation occurred by trunk lengthening but not head and tail lengthening. Additionally, contrary to other tetrapods, evolutionary axis elongation in crested newts was followed by a decrease in body size. We advocate the hypothesis that ecology drives the evolution of body form in crested newts.     

蜡皮蜥的两性异形和繁殖输出

为研究蜡皮蜥(Leiolepis reevesii)两性异形和繁殖输出,于2002、2003年4月下旬从海南乐东一种群捕获423头蜡皮蜥。经检测得到繁殖雌体的最小体长为89．0mm,据此判定≥89．0mm的个体为性成熟。研究结果表明：①蜡皮蜥具有两性异形,雄性大于雌性且具有较大的头部。成体雄性头长和头宽随体长的增长速率大于雌性,幼体头长和头宽随体长的增长速率无显著的两性差异。以性别和年龄(成、幼体)为因子的双因子ANOVA比较两性头长和头宽与体长的回归剩余值发现,雄性头部大于雌性,幼体头部相对大于成体。②饲养于实验室的母体中有42头于2002、2003年5月22日～7月16日产出正常卵,这些繁殖雌体具有年产多窝卵的潜力。窝卵数和卵重的变异系数分别为0．18和0．13,前者变异度大于后者。窝卵数、窝卵重和卵重均与母体体长无关。卵重与相对生育力之间无显著的负相关性,表明蜡皮蜥缺乏卵数量与卵大小之间的权衡。相对窝卵重与母体体长呈显著的负相关,表明较小的母体具有相对较大的繁殖输出。因雌体繁殖会滞缓其生长,小母体具有相对较大的繁殖输出,至少部分地解释了雌性蜡皮蜥的成体为什么个体较小。     

Sexual and male horn dimorphism in Copris ochus (Coleoptera: Scarabaeidae)

Copris ochus (Coleoptera: Scarabaeidae), an endangered species, is the largest dung beetle in Japan. In C. ochus, males have a long head horn, while females lack this long horn (sexual dimorphism). Very large males of C. ochus have disproportionately longer head horns than small males, suggesting male horn dimorphism, although the dimorphism has not been investigated quantitatively. To clarify sexual and male horn dimorphism in C. ochus quantitatively, we examined the scaling relationship between body size (prothorax width) and head horn length in 94 females and 76 males. These beetles were captured during July 1978 from a natural population on Mt. Aso in southwestern Japan using a light trap. Although the horn length of the females and males scaled with prothorax width, the scaling relationship differed between the sexes, i.e., the relationship was linear in females and nonlinear in males. Statistical tests for dimorphism in male horn length showed a significant discontinuous relationship, thus indicating distinct sexual and male dimorphism in head horns. Long- and short-horned C. ochus males may have different reproductive behaviors, as described in other horned dung beetles.     

Relationships between body size and biomass of aquatic insects

SUMMARY. Predictive equations were developed to estimate dry weight from body length measurements for forty-three taxa of aquatic insects. The inter-relationships between dry weight, body length and head capsule width of individuals grouped according to the eight major orders of aquatic insects were also examined. Regression analysis indicated that the relationship between biomass and body size was best expressed by a power equation, Y =_aX^b, rather than by linear or exponential equations. Changes in body length versus head capsule width were best expressed by linear equations, with three distinct relationships being observed. Body length estimated biomass better than head capsule width. Populations often species of insects collected from two different rivers generally did not differ significantly in their dry weight to body length relationships.     

浙江丽水虎纹蛙形态特征的两性异形和食性

用数显游标卡尺测量了407只2001—2003年9月下旬至10月上旬浙江丽水罚没的死亡虎纹蛙的体长等10个形态指标,结果表明:雌性成体体长(SUL)大于雄性成体,幼体形态无显著两性差异;ANCOVA去除SUL差异的影响后,雌性成体的头长和后肢长大于雄性成体,前肢长、眼径和耳径则小于雄性成体。前肢两侧对称性的偏移度成体大于幼体,雌性大于雄性;后肢两侧对称性成幼体和两性无显著差异。10个形态指标主成分分析的前三个主成分共解释64·6%的变异:第一主成分中头宽、眼径和耳径,第二主成分中后肢长,第三主成分中眼间距和鼻间距分别有较高的正负载系数。用NikonSMZ-1000解剖镜鉴别277只个体胃内容物中的食物种类,发现其秋季食物以节肢动物为主;成幼体和两性食物生态位宽度为3·42~5·25,食物生态位重叠度较高为0·93~0·98。分析表明,虎纹蛙局部形态特征的两性差异微弱,而体长两性异形差异显著;雌体具有较大的体形与食性无关,而可能与生育力选择的作用有关。     

Growth and development of the Tasmanian devil (Sarcophilus harrisii) at Healesville Sanctuary,Victoria, Australia

A study of the growth and development of the Tasmanian devil (Sarcophilus harrisii) was undertaken on a litter born at Healesville Sanctuary in Healesville, Victoria, Australia. Measurements of crown–rump length, head length, and head width were recorded every week from birth. Body weight was recorded weekly once the joeys were detached from the teat at 142 days of age, until 218 days of age. The growth curves revealed an initial linear increase in crown–rump lengths until approximately 60 days of age, when the gradient increased, while head length and head width showed a largely linear increase with age. The appearances of various morphological characteristics were also recorded. Zoo Biol 22:497–505, 2003. © 2003 Wiley‐Liss, Inc.     

麦双尾蚜的龄期鉴别

麦双尾蚜Diuraphis noxia (Mordvilko)无翅孤雌蚜的体长、体宽、头宽、腹管宽、上尾片长、尾片长和触角节Ⅲ长等7个形态指标,在各龄期间差异显著。根据麦双尾蚜的翅、翅芽、触角节数、尾片形状、上尾片长与宽比值等特征作为龄期鉴别的主要指标,编制了麦双尾蚜龄期鉴定检索表。     

松墨天牛成虫雌雄体型差异及蛹和成虫大小与越冬幼虫体重的关系

【目的】本研究旨在明确松墨天牛 Monochamus alteratus 成虫及越冬幼虫体型大小的差异,探讨该虫越冬后成虫体型大小和越冬幼虫体重大小关系及原因。【方法】于2014年5月1日至10月31日在浙江富阳野外诱捕松墨天牛,通过测量野外诱捕到的松墨天牛成虫体长、体宽,确定林间松墨天牛成虫体型的差异;松墨天牛越冬幼虫的采集和称重测量明确越冬幼虫的组成和体重大小差异;进而通过对越冬幼虫单头跟踪饲养至化蛹、羽化,确定越冬幼虫体重大小与发育所得蛹和成虫大小的关系,阐明林间松墨天牛成虫体型差异的原因。【结果】浙江富阳野外诱捕发现,松墨天牛的活动期间很长,从5月中旬到10月初一直能诱捕到松墨天牛成虫,高峰期在6和7月份。松墨天牛雌雄成虫体型差异很大,雌虫平均体长和体宽分别为20.59±0.19和6.59±0.06 mm;雄虫平均体长和体宽分别为19.90±0.26 和6.44±0.08 mm; 雌虫的平均体长明显高于雄虫,但二者体宽没有显著差异;并且雌雄成虫体长和体宽呈显著正相关。越冬幼虫的头宽测定表明头宽的变化很大,最小为2.20 mm,最大为4.24 mm,经比对越冬幼虫由4龄和5龄幼虫组成;幼虫体重差异大,平均体重为304.2 mg, 介于71.6~858.0 mg之间,其中5龄越冬幼虫显著重于4龄越冬幼虫。进一步将越冬幼虫单管饲养跟踪研究发现,越冬幼虫体重大小决定蛹和羽化后的成虫的大小,二者存在显著的正相关,并且由4龄越冬幼虫发育所得的蛹和成虫显著轻于由5龄幼虫发育所得的蛹和成虫。【结论】松墨天牛成虫体型差异很大,这与越冬幼虫体重差异相关;越冬幼虫的体重大小决定了其化蛹后的蛹重和羽化后成虫的体型和体重的大小;造成越冬幼虫体重差异的可能原因包括松墨天牛成虫扬飞周期长导致的产卵期长而使得天牛发育进度不一致以及寄主不同部位营养的差异。     

The effect of age on the morphometric sperm traits of domestic pigs (Sus scrofa domestica)

The experiment was conducted using 20 male domestic pigs, which were in 2 (equal-sized) age groups: under 14 months old and over 18 months old. At least 5 ejaculates from each male were taken, and in each ejaculate, morphometric measurements of 50 spermatozoa were made. The measured parameters were head area, head length and width, and flagellum length. For each ejaculate, the basic physical traits and the frequency of occurrence of developmental anomalies of the spermatozoa were examined. It was found that sperm dimensions tended to increase along with the boars' age. Considerable and statistical differences in head area and flagellum length were proved. Spermatozoa collected from older boars (above 18 months of age) had a head area larger by 0.49 microm(2)(P< or = 0.01) and a flagellum longer by 0.67 microm (P< or =0.01) than spermatozoa collected from younger boars (under 14 months of age). The differences in head length and width between the spermatozoa of the tested boars were considerably smaller and were not statistically provable. Significant correlations between the head area of spermatozoa and the head length (r = 0.56, P< or =0.05) and head width (r = 0.36, P< or =0.05) were found. However, the head length was not significantly directly correlated with its width (r = 0.18, P< or =0.05), and flagellum length was negatively correlated with spermatozoan head width (r = -0.71, P< or =0.05). Slight correlations between the morphometric traits of the sperm and the physical traits of the ejaculates (r = -0.11 to 0.16) were found, although in most cases, the correlations were not statistically provable.     

Effect of prenatal gamma irradiation during the late fetal period on the postnatal development of the mouse

Pregnant Swiss albino mice were exposed to 0.3, 0.5, 1.0, or 1.5 Gy of gamma radiation on day 17 of gestation. Sham-exposed controls were examined for comparison. Exposed mice as well as controls were left to complete gestation and parturition. Pups were observed up to age 6 weeks; appearance of physiological markers (pinna detachment, eye opening, fur development, vaginal opening, and testes descent), postnatal mortality, body weight, body length, head length, head width, and tail length were recorded. A significant delay in fur development was observed at 0.3 Gy and in other physiological markers at doses above 0.3 Gy, while a significant increase in mortality and growth retardation occurred only at 1.0 and 1.5 Gy. Although congenital anomalies such as syndactyly and bent tail were observed at doses of 0.5-1.5 Gy, only syndactyly showed a statistically significant increase in frequency. A statistically significant lower body weight was observed during the first week of postnatal life, but body weights increased to normal levels by the second week in animals exposed to doses less than 1.0 Gy. At higher doses, low body weight persisted throughout the postnatal period. Head length and tail length showed a significant decrease from controls at 0.5-1.5 Gy, and the effect was evident from birth to age 6 weeks. But a similar effect on body length and head width was noticed only at 1.0 and 1.5 Gy. These studies indicate that even in the absence of any major morphological changes, normal development of physiological landmarks and postnatal growth can be impaired by fetal irradiation at 17 days p.c. (post coitus). Morphological changes appear to have a threshold between 0.3-0.5 Gy, while physiological marker effects may occur with a lower threshold.     

海南紫斑环蝶形态特征及生物学特性观察

【目的】明确海南紫斑环蝶Thaumantis hainana各龄期的形态特征和生物学特性以及寄主植物。【方法】野外采集海南紫斑环蝶雌成虫,通过三角袋内套卵的方式获得受精卵。采用恒温饲养箱,在26℃、相对湿度40%、光周期16L∶8D下利用获得的卵供以美丽针葵Phoenix loureirii,饲养幼虫,并进行形态特征的观察,记录其各龄幼虫的体长与头壳宽,以及其他各龄期的部分形态学数据。【结果】海南紫斑环蝶共经历卵、幼虫、蛹、成虫4个龄期。卵圆球状,光滑,直径2.5~2.8 mm;幼虫5龄, 随着幼虫龄期的增长,体长与头壳宽度逐渐增加;悬蛹;成虫雌雄同型。【结论】本研究基本明确了海南紫斑环蝶各龄期的形态特征,并观察了部分生物学特性,确定了海南紫斑环蝶的一种寄主植物为美丽针葵,完善了该物种的基本资料。     

The evolutionary history of Drosophila buzzatii. XX. Positive phenotypic covariance between field adult fitness components and body size

In the cactophilic species Drosphila buzzatii, it is feasible to infer the action of natural selection by simultaneously sampling different life history stages in the field. During four years of research, samples of mating and non-mating adults and pupae were taken from a natural population. The main adult fitness components, i.e., mating success, longevity, and fecundity, were recorded in relation to body size, as measured by thorax length. The age of flies was estimated by observing the developmental stage of the reproductive system. Our data showed that larger flies can outlive and outmate small flies, and that mating success is related to age. An estimate of the fitness function showed a linear increase of mating success with increasing thorax length. There was no assortative mating for this trait. We advance the hypothesis that mating success is related to the rate of encounter and courtship time through general activity, which in turn may be related to body size. A positive phenotypic correlation between thorax length and ovariole number, which is related to fecundity, was found in females emerged from wild pupae. Neither the phenotypic nor the genetic (additive) correlations between these two traits were statistically different from zero in laboratory reared females. The genetic consequences of the observed phenotypic selection on body size are discussed.