Unit 4 Blog Entry

 

Vocab:
Species Richness- number of species in a given area

Species Evenness- relative proportion of different species in a given area

Microevolution- evolution occurring below the species level

Macroevolution- evolution that gives rise to new species, genera, families, classes, or phyla

Evolution by Natural Selection- change in the genetic composition of a population over time as a result of the environment determining which individuals are most likely to survive and reproduce

Evolution by Artificial Selection- change in the genetic composition of a population over time as a result of humans selecting which individuals breed, typically with a preconceived set of traits in mind

Allopatric Speciation- process of speciation that occurs with geographic isolation

Sympatric Speciation- evolution of one species into two, without geographic isolation

Genetically Modified Organisms- organism produced by copying genes from a species with a desirable trait and inserting them into another species

Fundamental Niche- suite of ideal environmental conditions for a species

Exponential Growth Model- growth model that estimates a population's future size after a period of time, based on the intrinsic growth rate and the number of reproducing individuals currently in the population

Logistic Growth Model- growth model that describes a population whose growth is initially exponential, but slows as the population approaches the carrying capacity of the environment

Carrying Capacity- limit of how many individuals in a population the food supply can sustain
 

Keystone Species- species that is far more important in its community than its relative abundance might suggest

 

Current Event:
Biodiversity Hotspot- biogeographic region with a significant reservoir of biodiversity that is under threat from humans; they are important because they contain a large amount of genetically varied species but could be destroyed
My hotspot is located in the Caribbean Islands and it has ecosystems ranging from montane cloud forests to cactus shrublands 
Endemic Species- species restricted to a certain area; Caribbean mahogany and Cuban solenodon
Deforestation is a huge problem there and is causing destruction of the only habitat most of the species can live in; the bringing in of certain alien species that invade, push out the native species
Efforts have been made to try to make certain areas protected and made into conservations

Pick A Side:
The fundamental niche of a species can both provide a perfect ecosystem and use a perfect ecosystem needed for life to survive. If more species can reach this than the species richness will increase. If the keystone species can undergo enough microevolutions to best fit the location than the ecosystem will follow the logistic growth model until the carrying capacity is reached.

Big Picture Reflection:
Human Impact- Humans can change the way species are when they artificially modify specific organisms into their own desirable species. They can also cause geographic isolation when they cut down trees and destroy parts of ecosystems.
Environmental Impact- When an organism reaches its fundamental niche it can rise up to the carrying capacity allowing for it to be preyed on more or allowing it to control other populations. Through natural selection, species could prosper or die off.
Economic Impact- When new breeds are introduced with artificial selection, they can be sold for higher prices than previous, more common breeds.
 Government Legislation- Laws are put in place to protect environments such as the biodiversity hotspots mentioned above. The efforts to keep the species richness up have grown in numbers over the years as more species reach endangered status.