A Rostrata Hypothesis

Alterations of environmental conditions appear constant to aquatic organisms that live within rocky shore ecosystems. The Zebra-top Snail was examined species within the following report, found on intertidal rocky shores of south-east and West Australia. The reaction and mass change of the Zebra-top Snail was examined whist carrying out this experiment. It was hypothesised that the Snails placed into higher salinity water will attempt to find higher ground, and their mass will be less than their original weight. The Snails were placed in water, each containing different amounts of salinity, as the rate of reaction was examined. The Snails placed in greater salinity showed a significant response in reaction within 10 minutes of observations.

Given these simple characteristics, isopods are of great and easy use for scientific studies. The goal of the first experiment was to determine whether or not isopods prefer a moist environment or a dry environment. This led to the hypothesis that isopods have a preference between wet or dry environments;

Pill bugs, Armadillidium vulgare, are terrestrial isopods [Gibbs, Smigel, 2008]. Thus, they are not very well adapted to land [Gibbs, Smigel, 2008]. Water loss is a reoccurring theme because terrestrial isopods lack “cuticular lipids and the elaborate spiracular apparatus of insects” [Gibbs, Smigel, 2008]. Most of the water loss is evaporation from the respiratory organs [Gibbs, Smigel, 2008]. The respiratory organs are called pleopods, and are gill-like organs “located on the ventral abdominal segments” [Gibbs, Smigel, 2008]. Interestingly, pill bugs are capable of conglobation, the ability to roll up in a ball [Gibbs, Smigel, 2008]. In addition to protection from predation, conglobation may also conserve water [Gibbs, Smigel, 2008].

Purpose: The purpose of this lab is to observe the behavior of the Armadillium vulgare (roly- poly

The crayfish differs from the earthworm and the chordate because it has a hard exoskeleton that covers its body.

This experiment is to see The Affect of Caffeine on Daphnia. Daphnia is also known as a water flea. It is a distant relative of crabs and shrimps. (Marshall Cavendish, 2002) Daphnia have a hard external skeleton with jointed appendages and limbs. The head contains a large central eye which is made of two eyes joined together. Daphnia has two pairs of antennae which are used for swimming. Each daphnia has five pairs of limbs. These limbs lie in a certain space under the body bounded by the carapace. (Marshall Cavendish, 2002) A carapace is a hard upper shell or chitinous outer covering on the back of some animals. The daphnia is well preserved because of its shells which are composed of chitin. The usual size of this microorganism is about 0.2-0.3 mm; they look like flat disks. Their bodies are divided into three parts – head, thorax, and abdomen. The head is typically dome-shaped with five pairs of appendages. Among these five are two pairs of antennae; there is a small pair and a larger pair. The smaller pair of antennae serves as a sensory function and the larger one is used for swimming. The other three appendages’ purpose is to secure food they intake. (Michael Hutchins, 2003) The thorax holds four to six pairs of legs that are used for gathering food, filtering water, or grasping mates. There are over 400 species of daphnia and they are distributed worldwide. Daphnia uses their thoracic legs to produce a constant current of water; this allows them to filter food

Discussion The speed and distance of a garden snail, or Helix aspersa, depends on multiple factors however, a main factor is the surface they are on. In our experiment, the snails moved much quicker and farther on the Rite-in-Rain paper when compared to sandpaper. Throughout their lives, snails will be traveling on different types of surfaces for example, snails will slide through smooth, gentle surfaces such as plant leaves and they will push through course and permeable surfaces such as wood. It is important to know how different factors can affect the results.

I. In the wild, the deep water supports the dorsal fins upright position while collagen hardens, and in captivity, the pool water isn’t deep enough to exert the amount of pressure necessary so the fin bends.

Both of these factors gave the Orohippus greater grinding ability, suggesting it consumed tougher plant material and not grass.

The purpose of this simulation is to see how these three organisms will interact with one another in the same environment. We will see how the populations of these organisms change by modifying parameters specific to each organism and how changing

because it is made up of tiny teeth-like structures called placoid scales, also known as dermal denticles. These scales point towards the tail and help to reduce friction from surrounding water

Furthermore, group swimming behaviors of Atlantic salmon or Salmo salar L. show to be affected by flow velocity as well. In an experiment, a group of Salmo salar L. were placed in a cage and were exposed to low, medium, and high flow velocities. Swim group structures were characterized as circular polarized swimming (circle), swimming facing the current (on current), or swimming in combination of the circle and current patterns (mixed). Results showed that the group of Salmo salar L. displayed circle swimming arrangement under low flow velocity conditions, mixed swimming arrangement with medium flow velocity, and on current arrangement with high flow velocity. As flow velocity increased, the group of Salmo salar L. would alter swimming behavior from schooling to swimming against the current and resided near the walls of the cage (Johansson et. al. 2014).

The duckbill platypuses have broad bodies covered with fur and flat tails that help with swimming. The bill of the platypus has many nerves including watertight nostrils that provide them with an advantage of breathing underwater. The morphology of duckbill platypus consists of short forelimbs and webbed hind feet that help the platypus thrust itself through water. Platypuses have fat stored in their tail with claws on their feet that helps them move and borrow on land. Another morphological feature that platypuses have acquired is the retraction of webbing on their feet and exposure of nails.

Cnidarians share a basic body plan, but have two distinct body forms-the polyp and the medusa. The medusa plan is essentially the polyp turned upside down. By inverting same shape, cnidarians devised two distinctive ways of living. Exactly how and when the transition occurred is uncertain, but anchored cnidarians adapted a body plan for a free-swimming life (the medusa),and may have been the first animal to swim the oceans. The medusa plan allows the jellyfish to swim through the water using muscle contractions and float with the currents.

Rostow identifies five stages of economic development. The traditional society is characterized by the dominance of agriculture, which is largely at the subsistence level, and the non-realization of potential resources. In the second stage, economic growth begins to speed up. There is an expansion of trade, perhaps an increase in external influences, and an introduction of modern methods of production, which are used along the more traditional techniques. The take off stage occurs when old traditions are finally overcome, and modern industrialized society is born. Investment rates rise from five percent of national income to ten percent, one or more major manufacturers emerge, political and social institutions are