Orca 2

Submitted by cwcasey on Tue, 12/04/2018 - 13:21

The social structure of killer whales is very distinct. When focusing on resident killer whales specifically, it is important to note that the basic social unit is called a matriline. This is a group of killer whales which are connected by maternal descent. This core group is highly stable with bonds that are extremely strong. Individuals are rarely seen apart for more than a few hours. Studies conducted have shown that individuals have not been seen to permanently leave any of these observed resident matrilines. Matrilines may consist from 1 to 4 generations of related whales. Pods are the next social structure - which consist of related matrilines that travel and hunt together. Pods are less stable and it is not unusual that a matriline will break away from the pod for an extended period of time. Beyonds pods, are clans. Clans are made up of pods with similar vocal dialects, and may be related. Pods may have developed from one ancestral pod which fragmented over time. Pods from different clans are frequently seen traveling together. The last social level is a community. Whales do not share common maternal links or vocal similarities, but simply share a geographic range.

    Similar to resident killer whales, the matriline is basic social unit in transient whales. However they are typically smaller in size, and juvenile and adult offspring can disperse for long periods of time or even permanently. Consistency in grouping patterns is not common. Associations are more dynamic in transient killer whales as well.


draft 2

Submitted by fmillanaj on Tue, 12/04/2018 - 13:00

Several different studies described spider webs as depending upon the mechanical performance of capture threads, and states that web function arises from the architecture and mechanical performance of silk (2). This study also used microscopy, and measured the web thickness of different web types: orb webs, funnel webs, dome webs, and irregular mesh webs. The different types of webs yielded different thicknesses on average, with orb webs being the thickest. Since spider webs must be strong enough to withstand the weight of the spider on the web, and be durable enough to support the spider’s movement, it is plausible that spider weight could also be a factor in web thickness, in addition to web type.  


Orca 1

Submitted by cwcasey on Tue, 12/04/2018 - 12:56

Orca whales - also known as “Killer Whales” or Orcinus Orca, are one of the world’s most powerful predators. They are often found in cold, coastal waters but can be found from polar regions all the way to the equator. Orcas are known to feast on many marine mammals such as seals, sea lions, and other whales. They also eat fish, squid, and sea birds. A notable part of the Orca’s lifestyle is their hunting technique - in which they hunt in deadly groups of 5 to 50 whales, called “pods.” There are three subgroups of orcas; residents, transients, and offshore orcas. We will focus our attention on Residents and Transients, as they have the most research conducted on them. A resident pod can include from 5 to 50 Orcas. A transient pod usually consists of 1- 6 Orcas. The difference in pod sizes is likely to due to the subgroups’ feeding habits. Resident pods typically feed on fish, specifically salmon. Resident orcas herd schools of fish to get their food, and this method is most effective with a large number of orcas. Transient orcas prey mainly on marine mammals. This can be a time-consuming, demanding process as the orcas must cooperate to sneak attack their prey. Hence why their pods are smaller in size.

    The act of cooperative hunting is a distinct and unique process in which many factors come into play. Transients are generally more quiet when communicating. This may be due to the fact that they are hunting marine mammals, and must approach them quietly to avoid being detected. Transients use echolocation - but only in single clicks. Transient pods in the same region, communicate with simple language and do not vary in dialects. Resident Orcas are typically more vocal, relying heavily on echolocation to find their prey. Because their main food source, salmon, does not have good hearing, they do not have to worry about being quiet. Each Resident pod has their own set of complex calls.


Lobe finned fishes

Submitted by mtracy on Tue, 12/04/2018 - 12:17

Sarcoptyrigians includes all lobed finned fishes and is one of the two classes in which all boney fish are seperated into. Sarcopterygians can be further split into at least lineages: the dipnoi and the actinistia. There are several characteristics which unites all sarcoptyrigians. They have monobasic paired fins, that is, their fins only have one bone connecting the fins. Furthermore, these have muscular fin bases. Their teeth are covered in enamel. Lastly, all sarcoptyrigians have at least 4 bones comprising their sclerotic ring around the eye. Technically, we can even classify a human as a Sarcopterygian, despite it not being a "fish." This is because we, like the sarcopts, have lobed fins. Furthermore, we have enamel on our teeth. It should be noted that the 4+ rings around the sclerotic ring is often reduced or completely absent in mammals.

Research Project - Research Design Draft Part #1

Submitted by sbrownstein on Tue, 12/04/2018 - 12:08

There are six possible projects that can be carried out, manipulating different variables in order to see how it affects spider web production and location. Although the six projects have different variables, they all contain one spider, are observed once a day; every morning, for two days, and feed flies every morning. During the daily observations, the observer should record any presence of webbing and its location in a style depicted in Table 1. 



Submitted by amdicicco on Tue, 12/04/2018 - 10:48

To collect data we took measurements once a day for eight days in a row. Everyday we collected two measurements. The first measurement was what color side the spider was on when we first entered the room and before interacting with the spider. The second measurement was taken after moving the spider to the middle of the tank where the colors met. We gave the spiders a ten minute rest period before taking and recording the data on which color side background the spider chose.


Submitted by amdicicco on Tue, 12/04/2018 - 10:42

We used two spiders in our experiment, and each was given its own tank. One spider was placed in yellow versus white tank, and the other in cyan versus green tank. The color backgrounds in the tanks were split right down the middle and the other factors including light entering, materials and temperature were kept constant between and within the tanks.


Submitted by amdicicco on Tue, 12/04/2018 - 10:42

We chose to test the colors white versus yellow and cyan versus green in our experiment. Some species of crab spiders are able to change their color from white to yellow, and yellow to white. We decided to use white and yellow as a control in our experiment and see which side the spiders would prefer. The color white is made up of red, green and blue all at their highest intensities which is 255 in the RGB color model. Yellow is made up of red and green both at their highest intensities of 255, with no blue is added. The next set-up contained cyan and green. Cyan is made up of green and blue both at their highest intensities of 255, and no addition of red. Green is made up of only green at its highest intensity of 255

GTP-tubulin draft

Submitted by curbano on Tue, 12/04/2018 - 10:32

While I know GTP-tubulin is what tells the microtubule to polymerize and GDP-tubulin tells the microtubules to depolymerize, I would assume something must initiate/signal the GTP or GDP to bind to tubulin. I am curious how this signaling system works and how the microtubule knows whether or not it wants to lengthen or shorten. Microtubules have a variety of important functions in the cell. They help with chromosome segregation, cell structure, cell movement, and directionality. The article does not say exactly how microtubules influence directionality, but I would think that the motor proteins, especially kinesin and dynein, play a large role in direction and movement.



Submitted by amdicicco on Tue, 12/04/2018 - 10:22

Ulva lactuca is an early colonist who has an effect on the later arriving Gigartina conaliculata. Figure 1 shows us that it is a facilitation relationship. Facilitation as a successional mechanism says that the early arriving species will make it less suitable for other early arrival species, but more suitable for late arriving species. This is seen in Figure 1 because when Ulva is present the number of Gigartina is much higher than it is when Ulva is removed.


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