Taborsky, Skubic, and Bruinties conducted a qualitative experiment on the effects of female N. pulcher egg size and clutch volume to the amount of helpers present (2007). In a given period, N. pulcher females reproduce around 100-300 eggs at a single time. Neolamprologus pulcher, which aid in protecting N. pulcher offspring’s, defend on average 36 offspring’s and in return are given an area to live for security. Two experiments were conducted to evaluate how fertile N. pulcher females react to intraspecific competition, the changes of egg size in the presence of increased Neolamprologus pulcher as well as how the young adapt to the environment they are raised in. In the first experiment, the fertility rate of N. pulcer females was recorded
Abstract: The house cricket, Acheta domesticus, was used to test whether food and potential mates drive aggressive behavior. Male crickets were randomly selected in pairs and place into a cage to observe aggressive behaviors in the presence of no food, food, and female. The cage provided a confine area for the crickets to fight one another while the variables of food and female were used in attempts of increasing aggressive interactions between the male crickets. There was no significance found through this experiment due to a lack of data. It was discovered that the experiment would have to be done at a larger scale to be able to see any significance in the two variables.
Fruteau C, Range F, Noe R. 2009 Infanticide risk and infant defence in multi-male free-ranging sooty mangabeys, Cercocebus atys. Behavioral Processes 83, 113-118
The comparative study of The Odyssey and The Penelopiad is enhanced by the fact that Atwood's novella is a direct interpretation of Homer's text. The transformation of character across the shifting 2000+ years is a strong point of friction between the two texts. Lessons 3 and 4 have focused on the characterisation of major (and some minor) characters in each text. Now it is your chance to examine the similarities and differences between the texts.
The Longnose gars reproduction depends on location that the gar is found in. The reproduction does typically happen during the spring or summer months and all dependent on what the water temperature. The female gar will swim into a small, fast moving stream and lay their eggs (Goddard). The Longnose gar eggs are not just normal eggs that most people think of when they think of fish eggs. Their eggs are green and sticky so they can stick to the plants in the fast moving stream (
The experiment can be improved by counting the number of eggs each gravid Artemia carries and the number of successfully born offspring to further support the hypothesis that the females fed on high nutrition have higher fecundity compared to the ones treated with low nutrition.
Soule, Michael E et al. “Ecological Effectiveness: Conservation Goals for Interactive Species.” Conservation Biology 17.5 (2003) : 1238-1250.
...to 300 individuals, the newborn seahorses are independent of parental care and the male is free to fertilize and accept more eggs(Lourie 11). The offspring bearing roles displayed by Hippocampus spp. is an extreme shift in relation to many other species of kingdom Animalia, of which the bearing of young is predominantly carried out by females. According to Foster, growth rates throughout the life cycle and the duration of the life cycle of seahorses in the wild varies between species and cannot be determined due to insufficient research data(foster 22). Once sexual maturity is reached, often determined by the presence of a brood pouch in males, adults are able to reproduce. During reproduction, the overwhelming majority of Hippocampus species display monogamous behaviors, usually mating with the same partner for the duration of the mating cycle(lourie 10-11).
Hopkins, in the east Kootenay region of British Columbia. I. Life cycle, brood development and flight periods. The Canadian Entomologist 94: 531- 538
because he felt she did not share his love for her. This poem is in
In Tacitus’ Germania, the author reveals different aspects of the Germanic tribes of that time. Tacitus underlines religion, politics, and warfare in his passages. He goes into detail about climate, geography, social structure, the different customs of the Germanic people, and the tribes that make up Germany. Warfare being described to be one of the most important characteristics of the Germanic people, it was the most respectable effort that people of Germany could display.
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.
Varricchio, David J., Frankie Jackson, and Clive N. Trueman. “A Nesting Trace with Eggs for
The female reproductive system in birds is reduced in most species to a left ovary and oviduct. This unilateral reduction of the female reproductive system is thought to bear two benefits: it reduces the female’s body and it prevent the potential problem of simultaneously carrying two large fragile eggs within the abdominal cavity. It also balances the body with the liver on the right side adjacent to the left ovary.
The first step was to obtain the White Rat and to tie it in the supine position, anterior surface facing up in side the dissection pan. To tie the animal, we used butcher’s twine and secured the front and hinds legs using a “lasso” technique, careful not touch the sharp claws. To make the first insicion I had to locate the Xifoid Process of the rat (distal aspect of the sternum). Once I had located the Xifoid Process, I had to use forceps to pull the skin of the animal’s abdomen up and use the scissors to cut. The first incision is made from stem to sternum, cutting through the errectos abdomen muscle down to the groin. The second incision ion is perpendicular to the first below the diaphragm. Because of this technique we were able to open the abdominal cavity first. The third and forth incisions were made bilaterally above the legs. The last two incisions were made in upside down “V” shape on the collarbone, to expose the thoracic cavity. This dissection was both sharp, because of the use of the scissors and scapel and blunt because of the use of the probe and forceps to move organs and skin to expose other organs not yet identified.
Behavioural hypothesis centres on protection of nest and the forming of the mating bond. (Mueller (1990) p. 553-585). This has similarities with the male mating theory.