In this lesson, we explore why animals live together in big social groups, and why others do not. At the end of the class we collect behavioral data on meerkats (Suricata suricata), and white-cheeked gibbons (Hylobates concolor) using instantaneous and continuous sampling. Lab Questions are answered at the end of class notes along with a link to my raw data set.
A pack of wolves, a group of orca whale, a pride of lions; why do some animals live together in a large group?
Leopards, praying mantis, red pandas; and why do some animals find it better to be single?
Animals interact in a variety of ways, the key to what works is what will benefit the individual the most, and you better beleive these benefits must outweigh the cost. Advantages of living in a large group gives you better defense against a predator, mutual defense, and can make hunting pray easier, but living with others doesn’t come without its disadvantages. Diseases can be passed easily when more individuals are around, and with more individuals it does become harder to be inconspicuous to your predators. The competition for resourcses, such as food and mates, becomes higher. Its easier to catch a mate if you are the only one there…
When you live in a group helping out can be a huge benefit to the individual. This discussion focuses on three main topics; cooperation, post poned cooperation, and reciprocity.
A simple way to explain Cooperation is when two individual both benefit from helping one another.Ex. Individual A (the helper) and individual B help each other right now and they both gain direct fitness.
Post Pone Cooperation
Post pone cooperation is when an individual eventually gains access to a resource controlled by another individual because of its prior help.
Reciprocity involves a interation where the individual was helped directly pays back the individual who helped them.
In your write-up, include copies of your data sheets, and those of your partner or a member of another group. Please address the following points.
1. The similarity between observers is called interobserver reliability. How similar were your observations to another student’s observations? How similar were they to the “researcher sample” observations?
When comparing my observations to Alex’s they were very similar, but did posses some differences. There was a variation of the times were we detected change in events in the gibbons, but what we perceived the subject to be doing were the same. We also had slight differences in the meerkat observation as to how many meerkats we thought were moving as opposed to foraging, and what we understood to be the act of being a sentry.
2. How do you explain any observed differences? Why is it important to minimize these? What could you do to maximize interobserver reliability?
Differences in observations can be attributed to many things. A key factor is viewer perception and perspective. If two observers were watching the meerkats as they scan and one meerkat is sitting on a rock the observes could perceive this in different ways, one may think that the meerkat is sitting up on its feet enough to be a sentry while the other observer things that the meerkat is resting. Another factor is the perspective of observers. If one sees the meerkat from the back hunched over one could think he is resting, but if one sees the meerkat from the front and can see it diggin, then they would mark him down as foraging. Finally, differences can come from the understanding of what can be described as each event. It is important to minimize these differences in observations, so that data can be consistant. To maximize interobserver reliability, each participant should be strictly guided on what they are looking for when deciding what event has occured.
3.Do you think it is possible to eliminate all interobserver variation? Elaborate.
I do not think it is possible to eliminate all interobserver variations because there will be some disagreements on what another observer has seen. There is always the chance one observer was not looking where or when the action happened.
4.What was the percent agreement calculated from the mock data?
The percent agreement calculated from the mock data was 0.9 or 90%.
5.What sort of questions about meerkat behavior could be addressed with the type of data that you collected? What about the gibbons?
The kind of questions that could be addressed with the data collected about the meerkats include; how many meerkats can feel comfortable to feed with one sentry, will the meerkats take turns being sentry, what other events happen during this time, how long does an individual stay at attention? For the gibbons questions the data addresses questions such as; how long does the baby gibbon move around before it needs to rest, is there more interactions between the baby gibbon and the mother or the father, what kinds of interactions are done more with the mother/father?