Journey of man #2

Yesterday in class we finished the movie journey of man. Here are some of the notes I took during the movie: 

-after Australia, our ancestors traveled to India 

- used costal route ( first costal migration from Africa) 

- 2nd group took route to Middle East (majority)  

- 1st wave went to India 

-2nd wave went to china 

- no trace of ancestors in Europe while they were populating Asia 

- found some causes for migration in cave paintings 

- ancestor taller than average man 

- by the time ancestors got to Europe, skin lighter

- because they moved into colder environments so skin needed to be lighter to allow vitamin D to synthesize 

- chuchi native Americans  are the ones that migrated form Asia to America 

- first arctic travelers 

- body shape adapted for cold weather 

- ice age created land mass that was connected to Alaska and used for migration to America 

- then traveled to South America 

One Page response:

The article “Does Race Exist?” by Michael J. Bamshad and Steve E. Olson, poses two main questions; can scientists use race to separate the human population into their genetic makeup groups? And can race be used to determine how a group in a population will react to certain diseases and medication? Both questions have been researched before but neither have a certain or clear answer.

            Question one has a few factor that make it hard to answer. The definition of race can have a different perspective in countries all around the world, making it hard to identify one’s actual race.  Additionally, one’s genetic makeup is controlled by more than one set of genes. In other words, just because your genes say you have brown skin, does not account for the rest of your genetic makeup. You could be more closely related to European ancestors than your African ones. To even begin to answer this question, scientists use DNA (specifically the base pairs) to determine the degree of similarity between two different people. While comparing DNA, scientists have also discovered and identified millions of polymorphisms. These tend to be neutral and show a history of natural selection. However, comparing these polymorphisms can be difficult due to the recent divergent evolution and mixed mating. Using the data collected during the comparisons of Alus (short strands of DNA) still can provide enough information to determine rough groups in a population. It turns out that yes, you can see racially influenced groups, but if you try to divide a main group into a sub group, in is almost impossible. An example would be India, who has been highly influenced by Europeans and East Asians, making it difficult to separate the India’s specific genetic makeup. Therefore, race cannot be of any help in determining these sub groups, for it is just a homologous feature as a result of natural selection. For scientists to be 100% accurate in their conclusion, they would need thousands of Alus from around the world, which is almost impossible to get currently.

            The second question also runs into a few problems. Doctors often take ones race into consideration when thinking about prescription medication or medical trials. They do so rightfully for it has been proven that certain races respond differently to diseases. An example would be HIV-1, the eventually leads to AIDS, has a slower progression rate in European- Americans than it does in African- Americans. There has been some controversy in using racial profile as a factor in the medical world because some view it as being racist, for they believe that the different responses to medication are negligible. Also, doctors have run into privacy and consent problems. However, it is generally accepted that for a doctor to use ones race as a determining factor in the medical world does have its benefits and could be important for one’s health.



Where did man come from?

Today in class we want over test questions and concepts. Then we want over the ideas covered in the National Geographic article we had to read for homework. My group talked about why some of the Native Americans refused to give their blood. The main reason was because it went against their religion and traditions, which is a problem that science (especially on the topic of evolution) runs into a lot. We also talked about how Native Americans now include a diverse selection of ethnicities, which makes it harder to determine their origin. This also means that they need a broad amount of blood samples in order to truly find a common ancestor; however, as I said before, not everyone wants to participate. 

Then we watched a movie called "the journey of man" about the man who was mentioned in the article we had for  homework. I took some notes on som of the main concepts: 

- Luca (another scientist) wanted to use blood to create family tree

- isolated tribes in Africa give best results because they are direct descendants an never left

- big question: how did they travel around the world so quickly? 

- San Bushmen- combination of all ethnicities 

- original language of ancestors 

- ability to think and contemplate things gave us an example of how we were able to conquer the world 

- why did cave men do when the sea shore moved back because of the ice age? 

- migration in search of food? 

- went to Australia next

- mango people have oration of history but not very reliable for historians and scientists 

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Test #2

We took a test today on unit 2 

It's mating season!

In class, we explored how dominant and recessive genes interact with each other.

Example of dominant trait: Aa or AA 

Example of recessive trait : aa 

Heterozygous: Aa 

Homozygous: AA and aa 

These combination of genes control what traits you get. The combination of genes that you receive come from your parents. More than one gene controls a trait 

These variations in species are what causes natural selection to happen. Thus, proving evolution at the same time. 

To make sense of the, two men named Hardy and Weinberg came up with a mathematical equation for all of this: P^2+ 2pq+ q^2=1

p+q=1. 

In class, we did a random selection of traits by walking around with gene cards and "mating" with other classmates. 

 

Take Home QUIZ:

 

1.) 

2.) 

Brine shrimp and natural selection

Today in class we want over the general concepts an data collected from the brine shrimp lab. We graphed the brine shrimp data using a simple line graph. This groups of egg's ideal salinity was 0.5, proven by the amount of eggs hatched in that solution. Our group of eggs however were not adapted to survive 1.0.  % salinity, causing an unusual dip in the line graph. The dip in the line graph could also be caused by human error. ( mixing of lids) 

We also brainstormed ways to expand the experiment: 

After this, we did a bead activity that used the pairing of random recessive and dominant  genes to show how natural selection works. The offspring with hh combination of genes died because they had no fur, while the combination of Hh and HH live on to pass on their genes. 

In the end, we learned that the recessive gene never goes away, no matter how random the pairings are. 

Then we also talked about other ways genes could be added to a community. 

Then we took a short quiz on natural selection. 

Adaptations and mutations

Today I class we went over the concepts of mutations and adaptations. Mutations can be negative, positive, or neutral. Organism with the positive mutations are more likely to survive and reproduce. This  mutation will become an adaptation after a few generations of that organism has reproduced. 

Then we did an activity with shells, and we organized them by their different characteristics. Some of the shells had holes that were drilled by the cone snail's tongue. 

Then we started our brine shrimp lab. 

Procedure:

- 30 ml of 0%,0.5%,1.0%,1.5%,2.0% of salt in a distiller water solution

- then you pour in you Petri dishes that are labeled 

- then you cut double-sided tape into 1.5cm and put it on each slide 

- then tap paint brush in brine shrimp eggs 

- then tap brush on tape

- place slide in solution 

- let it be for at least 24 hours