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Ctenophorus Caudicinctus
''Ctenophorus caudicinctus'', commonly known as the ring-tailed dragon or ring-tailed bicycle-dragon is a native species of agamid lizard occurring in rocky ranges and outcrops of Australia. ''Ctenophorus caudicinctus'' is most commonly found in the Pilbara region and offshore islands of Western Australia. The ''ctenophorus'' has 28 known species in the northern, southern, and western parts of Australia. It is recognized to be the most speciose group of Australian agamids. Description ''Ctenophorus caudicinctus'' are recognized for their bright colours, their survival tactics, and sexual dimorphism. Males display brighter colours than females to make themselves more attractive to a mate. The colour of the lizard is also impacted by their age, season, and temperature of their body. The ring-tailed dragon is about 25–35 cm long and is differentiated from other lizards by the line of spines that curves beneath the eyes. The pattern of the ''ctenophorus'' caudicinctus can ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Günther
Albert Karl Ludwig Gotthilf Günther FRS, also Albert Charles Lewis Gotthilf Günther (3 October 1830 – 1 February 1914), was a German-born British zoologist, ichthyologist, and herpetologist. Günther is ranked the second-most productive reptile taxonomist (after George Albert Boulenger) with more than 340 reptile species described. Early life and career Günther was born in Esslingen in Swabia (Württemberg). His father was a ''Stiftungs-Commissar'' in Esslingen and his mother was Eleonora Nagel. He initially schooled at the Stuttgart Gymnasium. His family wished him to train for the ministry of the Lutheran Church for which he moved to the University of Tübingen. A brother shifted from theology to medicine, and he, too, turned to science and medicine at Tübingen in 1852. His first work was "''Ueber den Puppenzustand eines Distoma''". He graduated in medicine with an M.D. from Tübingen in 1858, the same year in which he published a handbook of zoology for students of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoregulation
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature as its own body temperature, thus avoiding the need for internal thermoregulation. The internal thermoregulation process is one aspect of homeostasis: a state of dynamic stability in an organism's internal conditions, maintained far from thermal equilibrium with its environment (the study of such processes in zoology has been called physiological ecology). If the body is unable to maintain a normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs. Humans may also experience lethal hyperthermia when the wet bulb temperature is sustained above for six hours. The opposite condition, when body temperature decreases below normal levels, is known as hypothermia. It results when the homeostatic c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature Conservation Act 1992
The ''Nature Conservation Act 1992'' is an act of the Parliament of Queensland, Australia, that, together with subordinate legislation, provides for the legislative protection of Queensland's threatened biota. As originally published, it provided for biota to be declared ''presumed extinct'', ''endangered'', ''vulnerable'', ''rare'' or ''common''. In 2004 the act was amended to more closely align with the IUCN Red List categories: ''presumed extinct'' was changed to ''extinct in the wild'' and ''common'' was changed to ''least concern''. ''Near threatened'' was introduced as an eventual replacement for ''rare'', but the latter was to be phased out over time rather than immediately abandoned. The act is administered by the state's Environmental Protection Agency (EPA). There are provisions under the act which allow landholders to negotiate voluntary conservation agreements with the EPA. New regulations came into effect on 22 August 2020: Text may have been copied from this s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventromedial Hypothalamic Nucleus
The ventromedial nucleus of the hypothalamus (VMN, also sometimes referred to as the ventromedial hypothalamus, VMH) is a nucleus of the hypothalamus. "The ventromedial hypothalamus (VMH) is a distinct morphological nucleus involved in terminating hunger, fear, thermoregulation, and sexual activity." This nuclear region is involved in the recognition of the feeling of fullness. Structure It has four subdivisions: * Anterior (VMHa) * Dorsomedial (VMHdm) * Ventrolateral (VMHvl) * Central (VMHc) These subdivisions differ anatomically, neurochemically, and behaviorally. Function The ventromedial nucleus (VMN) is most commonly associated with satiety. Early studies showed that VMN lesions caused over-eating and obesity in rats. However, the interpretation of these experiments was summarily discredited when Gold's research demonstrated that precision lesioning of the VMN did not result in hyperphagia. Nevertheless, numerous studies have shown that the immediacy of hyperphagia an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Preoptic Nucleus
The preoptic area is a region of the hypothalamus. MeSH classifies it as part of the anterior hypothalamus. TA lists four nuclei in this region, (medial, median, lateral, and periventricular). Functions The preoptic area is responsible for thermoregulation and receives nervous stimulation from thermoreceptors in the skin, mucous membranes, and hypothalamus itself. Nuclei Median preoptic nucleus The median preoptic nucleus is located along the midline in a position significantly dorsal to the other three preoptic nuclei, at least in the crab-eating macaque brain. It wraps around the top (dorsal), front, and bottom (ventral) surfaces of the anterior commissure. The median preoptic nucleus generates thirst. Drinking decreases noradrenaline release in the median preoptic nucleus. Medial preoptic nucleus The medial preoptic nucleus is bounded laterally by the lateral preoptic nucleus, and medially by the preoptic periventricular nucleus. It releases gonadotropin-releasing horm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrasexual Competition
Male-male intrasexual competition occurs when two males of the same species compete for the opportunity to mate with a female. Sexually dimorphic traits, size, sex ratio, and the social situation may all play a role in the effects male-male competition has on the reproductive success of a male and the mate choice of a female. Larger males tend to win male-male conflicts due to their sheer strength and ability to ward off other males from taking over their females. For instance, in the fly ''Dryomyza anilis'', size shows the strongest correlation to the outcome of male-male conflicts over resources like territory and females. Influencing factors Sex ratio There are multiple types of male-male competition that may occur in a population at different times depending on the conditions. Competition variation occurs based on the frequency of various mating behaviours present in the population. One factor that can influence the type of competition observed is the population density of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oviparity
Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and monotremes. In traditional usage, most insects (one being ''Culex pipiens'', or the common house mosquito), molluscs, and arachnids are also described as oviparous. Modes of reproduction The traditional modes of reproduction include oviparity, taken to be the ancestral condition, traditionally where either unfertilised oocytes or fertilised eggs are spawned, and viviparity traditionally including any mechanism where young are born live, or where the development of the young is supported by either parent in or on any part of their body. However, the biologist Thierry Lodé recently divided the traditional category of oviparous reproduction into two modes that he named ovuliparity and (true) oviparity respectively. He distinguished the tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatogenesis
Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. This process starts with the mitotic division of the stem cells located close to the basement membrane of the tubules. These cells are called spermatogonial stem cells. The mitotic division of these produces two types of cells. Type A cells replenish the stem cells, and type B cells differentiate into primary spermatocytes. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II. The spermatids are transformed into spermatozoa (sperm) by the process of spermiogenesis. These develop into mature spermatozoa, also known as sperm cells. Thus, the primary spermatocyte gives rise to two cells, the secondary spermatocytes, and the two secondary spermatocytes by their subdivision produce four spermatozoa and four haploid cells. Spermatozoa are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertilisation
Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Processes such as insemination or pollination which happen before the fusion of gametes are also sometimes informally called fertilisation. The cycle of fertilisation and development of new individuals is called sexual reproduction. During double fertilisation in angiosperms the haploid male gamete combines with two haploid polar nuclei to form a triploid primary endosperm nucleus by the process of vegetative fertilisation. History In Antiquity, Aristotle conceived the formation of new individuals through fusion of male and female fluids, with form and function emerging gradually, in a mode called by him as epigenetic. In 1784, Spallanzani established the need of interaction between the female's ovum and male's sperm to form a zygote in frog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring-tailed Dragon (Ctenophorus Caudicinctus) (8851342177)
Ringtail, ring tail, or ring-tail may refer to: Animals Mammals * Ring-tailed cat, ''Bassariscus astutus'', a mammal of the raccoon family, in North America * South American coati, ''Nasua nasua'', also called the ring-tailed coati * Ring-tailed ground squirrel, ''Spermophilus annulatus'', of North America * Ring-tailed lemur, ''Lemur catta'', of Madagascar * Ring-tailed mongoose, ''Galidia elegans'', of Madagascar * Ringtail possums, the family ''Pseudocheiridae'', of Australia and New Guinea: ** Cinereus ringtail possum, ''Pseudochirulus cinereus'' ** Common ringtail possum, ''Pseudocheirus peregrinus'' ** Western ringtail possum, ''Pseudocheirus peregrinus occidentalis'' ** Coppery ringtail possum ''Pseudochirops cupreus'' ** D'Albertis' ringtail possum, ''Pseudochirops albertisii'' ** Green ringtail possum, ''Pseudochirops archeri'' ** Herbert River ringtail possum, ''Pseudochirulus herbertensis'' ** Lemur-like ringtail possum, ''Hemibelideus lemuroides'' ** Lowland ringt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skrjabinoptera Phrynosoma
''Skrjabinoptera phrynosoma'' is a parasitic worm in the phylum Nematoda, the most diverse of pseudocoelomates. Like many other parasites, the life cycle of ''S. phrynosoma'' is complicated and it involves two hosts – a lizard (e.g.: the desert horned lizard The desert horned lizard (''Phrynosoma platyrhinos'') is a species of phrynosomatid lizard native to western North America. They are often referred to as "horny toads", although they are not toads, but lizards. Description There are several imp ... ''Phrynosoma platyrhinos'' or the Texas horned lizard ''Phrynosoma cornutum'') and an ant. The interesting aspect of the life cycle of ''S. phrynosoma'' is that the parasitic worm adjusts its life cycle to that of both the ant and the lizard. During the middle of the mating season of the desert horned lizard ''Phrynosoma platyrhinos'', the female worm is already filled with the greatest number of eggs it can contain in itself. At the same time, the number of the ants acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arthropod cuticle, cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an exoskeleton, external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior Organ (anatomy), organs; it has an open circulatory system. Like their exteriors, the internal or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
