Introduction
In this research paper I will be discussing the Yellow-Bellied Three-Toed Skink and how instead of this reptile laying eggs like most reptiles would do, it is giving birth to live young instead. The Yellow-Bellied Three-Toed skink (Saiphos equalis) is a small reptile in size that closely resembles that of a snake, but with four legs. This specific species of skink can be found in New South Wales, Australia. It has been discovered that in the cold regions of New South Wales this organism is producing live young. However in the warmer regions of New South Wales this same exact species is laying eggs. (Handwerk, 2010). As stated in the National Geographic News, “Evolutionary records shows that nearly a hundred reptile lineages have
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Meaning that the babies are able to stay in a warm place for an extended period of time due to the geographic region that this skink is located in. So basically what the mother is doing is protecting her young. That idea is the root of what evolution is and makes perfect sense as to why scientist are saying that this organism is currently going through an evolutionary change. With that being said it is also believed that during this process the eggshell gets reduced to a much thinner one (Packard et al., 1977). This thin egg shell is then gone by the time the babies are ready to be born, thus the appearance of live birth. The normal skink egg shell is a thicker one that made up of proteins and …show more content…
The skinks that retain the eggs (produce live birth) were taken from the Southeastern part of New South Wales, and the skinks that laid eggs were taken from the Northern part of New South Wales (Smith and Shine, 1997; Linville et al., 2010). The skinks were then placed in a care facility at the University of Sydney in groups of up to 6 females in a glass aquarium set to room temperature at 20 °C. Each aquarium was provided with food, water, and a 25-W incandescent light bulb. (Stewart, 2010). The skinks were then euthanized and an oviduct was removed from each female so the embryo could be tested. Each embryo was then stained with one of the four protocols, 1. Hematoxylin and eosin, for general structure, 2. Alcian blue, for carboxyl and sulphate-ester groups of acid, 3. Periodic acid Schiff, for neutral hexose sugars, and 4. Dihydroxy-6, 6'disulfide-dinapthyl, sulphydryl and disulfide groups (Kiernan, 1981). The
3 Apr. 2014. The 'Standard' of the 'Standard'. http://eol.org/pages/323582/details>. Evans, Arthur V., Rosser W. Garrison, Neil Schlager, and Michael Hutchins. Grzimeks' Animal Life Encyclopedia.
On the first stage of development the litter could be of 2 to 7 minks. They are born blind and deaf with little to no fur. They grow reddish hair when they are 2 weeks old. When they are finally 5 weeks old their eyes will star to open in the mean time the mothers have to feed them and protect them from predators.
In reproduction, the female produces clusters of eggs that she carries in one or two egg sacs that are attached to her abdomen. Once hatched, The T. Californium’ life cycle has quite a few stages. The first being six naupliar (young) stages lasting 4 – 10 days. Next come the 6-copepodite stages (7-14 days for the first 5 stages) ending in the last stage where T.californicus is a sexually mature adult. Adults then live from 40 – 90 days after the stages are complete (Rickets and Calvin 1985).
The main evidence uncovered to support the main body of the article was observing the chicken reproduction to show how the egg was fertilized. In summary, I have discussed how the sperm and egg reproduce to create new individuals. I have also described the challenges with the sperm trying to reach the egg to reproduce, and how the egg only chooses the most optimal sperm for reproduction. Also, discussed how the protein affects reproduction and how they change over time since they are involved in reproduction. There is future research to gain more information on why there is sometimes reproductive failure.
The Eastern chipmunk is a small rodent of the Sciuridae family. This chipmunk is closely related to the red and grey fox, the flying squirrel, and the woodchuck. Its Taxonomic name is Tamias Striatus. The word Tamias, Means collector or keeper and Striatus refers to its bold stripes and coloring.
The courting ritual begins with the males circling females in an offshore mating ground and then the males approach and bite a female’s neck and if she accepts, they mate; if she does not accept, she swims to the bottom of the mating grounds (Deurmit L 2007). Males have long claws to use during mating because other males try to remove the mating male in order to mate with the female (Deurmit L 2007). Caretta caretta are polygynandrous and breed seasonally in the early summer (Deurmit L 2007). With mating, the females have the ability to store sperm throughout the reproductive season (Sakaoka K et al.). This characteristic developed with “changes in the sperm storage tubules (SSTs) in the oviduct” and allows the females to reproduce more (Sakaoka K et al.). This storage helps to combat climate change because Caretta caretta, as a species, only breed during certain temperatures (Sakaoka K et al.). Female loggerhead turtles have developed sperm storage abilities within mating to combat climate
The word “monotreme” is Greek for “one-hole,” referring to the cloaca that is the exit for the urinary, reproductive, and excretory systems (Dawson, 1983). The creatures are oviparous--the females lay eggs that develop outside of her body. This paper will explain the background of the animals, the anatomy of the tract and egg, breeding behavior, and genetics behind this unique reproductive system. It will pay special attention to the similarities of the monotreme reproductive system to those of animals we are more familiar with.
Nicholson KE, Harmon LJ, Losos JB. Evolution of Anolis Lizard Dewlap Diversity. PLOS ONE. 2007
The specifics of the skinks mating behavior and habitats during breeding season is unknown. They have a low fecundity, with one to five skinks born in a litter, with one litter born per year. The skinks are born in December (December, January, and February being the Australian summer months) and because they are ovoviviparous they give birth to live young rather than eggs that would hatch outside the body.
The reptiles show a very wide variety of animals that show either crypsis or aposematism. The Bothriechis schlegelii (Eyelash pit viper) is an example of a snake that is highly toxic. The snake’s venom (poison) is being injected into its prey to immobilize it quickly. The B.schlegelii has a wide variety of colors including yellow, green, brown and even pink. Its coloration has no specific relation to advertising its toxicity form other predators or hiding, however, it is used for hunting (Sinnett 2011). The Anolis carolinensis is a species of a non-toxic reptile, yet it shows change in coloration. The change in coloration can be stimulated by various factors such as excitement, temperature, lighting and shade on the background behind the animal. The ability to change colors is due to 3 layers of pigmented cells (chromatophores) providing 3 colors, blue, yellow and brown. The A.carolinensis can change its color by mixing the 3 types of chromatophores on the epidermis layer. By changing the outer more layer of its skin the A.carolinensis changes the visible light its skin absorbs or reflects. Even though it has only a few variations in color (green- brown) it uses these variations to camouflage itself in it’s own habitat (Losos 2012). These animals are only two species of a wide class of reptiles. Many members of this class show wide varieties of camouflages as means of protection. Others use colora...
Jacob, J., Pescatore, T., & Cantor, A. (2011, February). University of Kentucky. Retrieved from http://www2.ca.uky.edu/smallflocks/Factsheets/Keeping_guinea_fowl.pdf
The Eastern Indigo Snakes’ population has been slowly declining. They have been endangered since 1971. By the time an Eastern Indigo Snake is three to five years old, they are matu...
...ecial cells, the queen puts the eggs from which a new queen will emerge. After the larvae develop from the eggs, the cells are covered with wax.
...n from mid-January to early March. A few days before birth, females begin to collect material, such as brushwood, grass, and leaves, to build a nest, which is normally located in a hollow tree or a rock crevice. After a gestation period of 112 to 158 days, the female gives birth in mid-June to late July to one to four blind and deaf cubs weighing each.
One potential confounding variable is that the scissor beak, seen in chick number seven, could have resulted from genetic abnormalities. Although the scissor beak is commonly associated with genetic issues, the missing eye is not commonly found in addition to the scissor beak. Throughout the experiment the incubator was opened and closed several times. This could have resulted in an inconsistent temperature and humidity level producing difficulties