Tuesday, December 6, 2011

Biodiesel


Biodiesel is a substitute for diesel fuels which is used in trucks mostly in the United States. Usually soybean is used in the U.S. Vegetable oil and other natural oils are used to make biodiesel (used cooking oil). No petroleum is necessary but it can be mixed so that you have a blended biodiesel. It is available in all 50 states. It is better for your engine and makes the exhaust smell like french fries.

Benefits:
1) Better for the engine, environment, and human health.
2) New source of income for rural farmers-helps rural economies.
3) Simpler to make than ethanol and can be done right on a soybean farm.
4) Reduce smog, ozone reduction, acid rain, cancer, and asthma.
5) Burns 75% cleaner than normal diesel, reduce carbon monoxide, eliminates sulphur dioxide emissions. Reduction in greenhouse gases contributing to climate change.

Problems:
1) Sustainability issues with growing soybean. Increase of soybean deforestation or environmental changes may occur.
2) The efficiency in making biodiesel is not very good even though it is better than making diesel itself.
3) There are limits on production from land use, water availability, and competition of food crops.
4) Major technological advance would have to occur to completely replace diesel as the leading current source as compared to biodiesel.








Sunday, December 4, 2011

Mitochondrial Eve


Mitochondrial Eve is the maternal ancestor of all living humans. Mitochondria are the tiny organelles inside of human cells that contain their own genome. Each person's mitochondrial genome is inherited from his or her own mother making mitochondrial lineages maternal. The is one type of DNA within a humans body along with chromosomal DNA. Every human's mitochondrial DNA can then be traced back to one source so all humans would then be related. It is important to emphasize that there was not only one woman living at that time. This woman has been estimated to have lived 150,000 to 200,000 years ago. Many other women are believed to have lived during this time. It is not known why there is only one mitochondrial DNA strand of humans today.

With all humans being related genetically, why then do we have a diversity of looks ago people such as skin color, hair color, eye, color, face shape, etc? We would attribute human differences to evolution. Just like the evolution we can study in species, humans have adapted to different environments over time. The mutations that occur in DNA through reproduction affect the next generation of species. We have natural selection, genetic drifts, bottleneck effects, and the founder effect from geographic isolation that plays into these changes. Overtime, the traits humans carry have been mutations that have survived over time as well as adaptations to our new environments.





 




Burgess Shale

The Burgess Shale is one of the earliest fossil beds with imprints of soft-parts located in the Canadian Rockies of British Columbia. It is made up of black shale. The importance of this area of land is great for scientists because it gives evidence of earlier species and how they evolved to the organisms we have today. Over 60,000 unique fossils have been found with arthropods being the most predominate. Worms, crinoids, sea cucumbers, chordates, and others with no shell. It is difficult to preserve soft-bodied organisms so the importance of the Burgess Shale is great. There seems to be an explosion of species all at once which would go against the slow evolution of species that Darwin had concluded. The phyla of species we have today almost all can be traced to the sudden emergence of species during the Cambrian period. Thus this gives evidence to refute the theory of all animals be connected to one another and gradually forming a variety of species from one organism over time. Some even find this as evidence for a supernatural being having created and placed fully formed organisms on the Earth.