Invasive Species

Today in class, we had a very interesting discussion about invasive species. Evey class member took in a set of five criteria used to evaluate how "mean" an invasive species was and five organisms that we evaluated using that set of criteria.
My criteria were:

1. It threatens the biological diversity of the ecosystem
2. Is adaptable to many conditions
3. High dispersal ability
4. Has fast growth 
5. Dominates over the existing species in the ecosystem it is inserted into

I evaluated the following:

1. Yersinia pestis (black/bubonic plague)
2. Vibrio cholera (cholera)
3. Batracochryditum dendrobaditis (cytrid frog fungus)
4. Beak and Feather Disease (BFDV)
5. Carcinus maenas (European Green Crab)

My goal was to concentrate on diseases, fungi, and animals that would not be very common in the discussion. However, I had a few shared points with classmates (notably Vibrio cholera). 

My winner was Yersinia pestis, because, out of the group that I assessed, it brought the most damage (1/3 of the European population), provides threats to the enviornment due to the fact that it could attack both humans and other small mammals such as mice and ferrets, is extremely adaptible (humans, some mammals and is facultative anaerobic), it has high dispersal ability (spreads exponentially once it is inserted in an enviornment without the ability to erradicate it), grows very fast and can kill a person in a couple weeks, and it dominates the area it is put into, leaving no room for other illnesses/bacteria.

In conclusion, I liked the discussion because it was entertaining and was an interactive way of learning about the ways in which invasive species affect the ecosystem and humans.

How Meat Eating Can be Bad for us All

     Living and being raised in Brazil can make it hard for a person to agree to the negative effects of meat. I remember that, as a child, almost every satrday or sunday lunch with the family would involve our greatly known churrasco. It is hard to admit it, but from my research, it is true: meat cannot be great for the enviornment or the world, due to the great amount of space and resources it requires, the emissions of methane gas, and the unequal distribution of grains to feed cattle that could be feeding people all over the world. Although meat can be bad for us and for the enviornment, it can also have positive effects and should not be completely abolished.
     Raising cattle is not an easy business; it envolves lots of space, requires constant feeding and medication. It was concluded that the meat to provide a single meal can level up to 55 square feet of rainforest (PETA), and that water consumption is two to five times greater in the raising of livestock than in the production of legumes (Popkin). Also, the cattle take in tons of grain yearly, and the meat is often infested with agrotoxins, hormones and medicine. Cattle also emit methane gas from their notorious bodily gases. It is accepted by the UN that "livestock is responsible for a full 18% of greenhouse gas emissions" (Ensha), which is more, even than the cars, airplanes and other forms of transportation. What is the biggest problem that arises in this topic is the fact that one single person's worth of meat would equal 45 to 50 people being fed if the same resources had been put into grains or legumes. (Lappé)
     Although all of this is true, the cattle also prove good for the world. They have positive effects on the pasture they graze in, making it more fertile and stimulating their growth by eating it. Their manure is what fertilizes the soil, which is extremely helpful for the development of the species of plants in the region they graze in and against desertification, because it keeps the soil fruitful. The cattle also help spin money around in the world, and have millions of jobs related to it today in the world (G1).
     Albeit, I believe that the cut in the production and consumption of cattle must be implemented, but not radically. The idea of the meatless monday seems interesting, and perhaps could be expanded into more days of the week. I believe that is less radical or extremist of an idea than to completely ban the industry from functioning.

Bibliography

• http://www.emagazine.com/archive/142
• http://www.peta.org/issues/animals-used-for-food/meat-and-environment.aspx
• http://archinte.ama-assn.org/cgi/content/short/169/6/543
• http://green.blogs.nytimes.com/2009/03/27/meat-vs-climate-the-debate-continues/?hp
• http://www.greenrightnow.com/kabc/2009/04/01/food-vs-the-environment-getting-to-the-meat-of-the-problem/
• http://www.smallplanet.org/
• http://timeforchange.org/are-cows-cause-of-global-warming-meat-methane-CO2
• http://g1.globo.com/

Indian Embassy Biodiversity

On another day in AP Bio class, we went to the Indian Embassy and collected a number of species of plants. We tried to collect as many as we could find, since we were going to "use it for something really cool in class".

Okay.

My partner, Lethicia, and I found roughly 16 different species and then, in class, we compared to what the IB biology classes found. There were a total of 193 plants counted and 3524 individuals found. Each team counted the equivalent to about a sixth of a square meter, and we found all of that!

You might still think that this fact solely does not prove that the place is biodiverse. If that is the case, we can simply use the Simpson Index for biodiversity. 

Homer and Marge walked in and took a look at the place. They also said it was pretty biologically diverse.

No, not really. The Simpson Index is a value, from 0 to 1, which determines the level of biodiversity in a region. It is a little counter intuitive, but the greater the biodiversity of a region, the closer to region it will be. It takes into consideration not only the different amount of plants found (193) but also their abundance (3524) Our region had a biodiversity index of 0.095! That is VERY SMALL! It is less than 0.1! 

To find this number, this was the formula I used.

Therefore, the Indian Embassy has lots of biodiversity, since the index was so small. Although, really, if you look at that place, you would never fathom this. Ever.

Which is why the Simpson's index is so cool. It is something that is not hard to determine and extremely basic, since everybody can count up the different plants and their quantity. Also, it helps the comparison between two different places and allows us to determine where we have more biodiversity.

Carl Linnaeus

Carl Linnaeus had many names: Carolus Linnaeus, Carl Linnaeus, Carl Von Linné and Carl Nilsson Linnaeus.
He was born in Småland, Sweden, in 1707. He was a physicist, botanist and zoologist, but he was best known for creating the foundations for what we use today for binomial nomenclature, being the father of modern taxonomy and of modern ecology. He studied at the Uppsala University and later wrote his book Systema Naturae. He was also a university professor at Uppsala after writing his book. 

Linnaeus' taxonomy was not based on subjectivity, although he always felt wonder for nature and loved it deeply. His taxonomy was based on the number and arrangement of plant reproductive organs.

In one time, he went to a small city in the Netherlands, where the mayor of that city showed him a "hydra" that was really a fake. Linnaeus discovered this and told everyone about it. Then, he fled the city, afraid of the mayor's wrath.
He was considered great at what he did. Look at what these men said about him:
Jean-Jacques Rousseau: "Tell him I know no greater man on earth."
Goethe: "With the exception of Shakespeare and Spinoza, I know no one among the no longer living who has influenced me more strongly."
August Strindberg: "Linnaeus was in reality a poet who happened to become a naturalist"

An interesting fact about him is that he came up with the lectotype for Homo sapiens.

Tree Measurements

Hey! So today, we will have little about my tree's measurements and why they are important:

• Height: it is important because we can then determine how much sunlight it recieves, differentiate it from others and, over an extended period of time, measure its growth rate. Here is how I measured my palm:

          I took the height in cm from my perspective about 8 m away, and placed that number over the distance    from my eyeball to the yardstick. To find the answer, I just cross-multiplied. This is what I ended up with:

                                      25 = height of the palm

                                      23         7.83 m

          Therefore, the height was about 8 m. This is a very tall palm, but not all of the trunks have the same                         height. Some trunks have about 1.5 m, while others, such as this, are up to 8m tall.

• A second measurement is "DBH", or "diameter at breast height". With it, we are also able to compare trees and observe how they grow over the years. Since my tree has 8 different trunks, I measured them all:

TREE NUMBER:	1	2	3	4	5	6	7	8
DBH(cm):	21	22	22.5	22.5	12	14	12.5	11.5

• The next measurement I made was the crown of the tree. A crown is the distance from one side to the other of the tree's largest spot horizontally. The crown also affects how much sunlight the tree will absorb and how much space it ocupies. If a tree is original to a dense forest, it is likely to have a crown less wide than that of a cerrado tree, for example.The crown of my palm was very heterogeneous, so I decided to measure it in three places. My results were 3, 3.5 and 2.5 meters. Averaged up, that gives us a crown that is large but not too much when compared to other trees, especially in this region.
• Then, we were able to use our school's cool new lab devices to measure leaf light absorption. Light absorption means how much light energy the leaf will absorb and how much will pass through it. That is important to know because it affects photosynthesis. The more light a tree absorbs, the more photosynthesis will occur. I measured light absorption in a new leaf, a "middle-aged" leaf, and an old leaf, and here were the results. L1 is for the light occurrence at the time (about 3 PM). L2 is for the light absorption of the leaves.

L1	84857	85231	40550	83947	77085	84187
L2	2145	3048	3577	3921	5139	6721

• The temperature in the soil is also important because of the homeostasis of the plant. It is fundamental to know what enviornmental conditions help it thrive because then we can help it grow. My measurements of the temperature 10 cm down the soil ranged from 28.5 ºC where the sun was shining to 23.8 ºC in the shade.
• Another thing that we must measure is the Ph of the soil. That is an important measurement to make because the Ph determines certain nutrient that will be avaliable in the soil. For example, Nitrogen is only avaliable to plants with a Ph above 5.5. My palm had a soil Ph of 6.61, which means it has avaliability for Nitrogen, Phosphorus, Postassium, Sulfur, Iron, Manganese, Copper, and Zinc, with some Calcium and Magnesium as well. The tree uses these nutrients to nurture itself, maintain healthy and grow.

Hey! Just as a final note, I was surfing around the internet and found a fun game that has to do with trees! In this game you must jump from tree to tree (measuring the distance) and make sure you jump on to a tree that can hold you! This is the time to apply the DBH knowledge you just got! Have fun :)

Jungle Jump Game