One of thing things that is common to all of mankind and has been for all of recorded history is the presence of musical ability and expression. Music has transcended throughout every era and every culture and has been constantly changing and evolving alongside with humans. It has played such a significant role in the…
Today’s modern cheetahs can run 60 mph to catch prey. Their ancestors could originally only run 20 mph. There was selective pressure in the environment of cheetahs that demanded for faster cheetahs to catch more prey because there was a battle for survival. There was variation in the ancestral population. Some cheetahs could run faster…
Humans have a large impact on the environment—pollution, land use change, climate change, etc. We are just beginning to realize that we also cause evolutionary change, and the consequences of this. Ecology and evolution are strongly interconnected. What Is Evolution? Evolution can be viewed as genetic change over time or as a process of descent…
What Darwin Observed Darwin sent specimens collected on his voyage back to England to be examined by experts Fossils collected were confirmed to be large versions of the present-day sloth and armadillo The Galapagos Island’s bird specimens were in fact many different species of birds Darwin originally thought they were just variations of the same…
Divergent and Convergent Pathways Once a new species forms, its evolutionary pathway may diverge from the original species. Disruptive selection continues long after speciation has occurred resulting in divergent evolution. Divergent evolution: occurs when two or more species evolve increasingly different traits, resulting from differing selective pressures or genetic drift. Species with significantly different morphological…
Random change Key factors that can cause evolution: –Small populations are more variable to changes in allele frequencies -non-random mating opportunities result in only those “preferred” traits being passed onto future populations –new alleles may be created when mutations occur (changes the frequencies of new and original alleles) -migration causes changes in the relative abundance…