Class notes
Class notes introductory biology (BIOL1010) Lesson 10
- Course
- Institution
Perfect notes for studying and allowing you to focus your time in class to new materials the professor gives out in order to create meaningful notes
[Show more]
Seller
Follow
nkohoot
Content preview
Evolution of PopulationsAristotle's scala naturae
● Fixed species
● Arranged on a scale of increasing complexity
Carolus Linnaeus’s classification
● Nested classification
● Grouping similar species into increasing general categories
● Pattern of creation
Mechanism for evolution
● By: Jean Baptiste Lamark
● Proposed model for how life changes over time
● Creatures have innate drive to become more complex
● Use and disuse
○ Parts of the body that are used extensively become larger and stronger,
meanwhile those not used deteriorate
● Inheritance of acquired characteristics
○ Pass these modifications to its offspring
● Researchers discards the idea as our understanding of genetics refutes the
mechanism
● Traits acquired by use are not inherited in such a way
The Origin of Species
● Describes Darwin's theory of natural selection by evolution or what he calls
descent with modification
● Natural selection: a process where individuals have inherited certain traits tend
to survive the reproduce at higher rates than others.
● Originated his theory on the Galapagos island on the HMS Beagle by looking
how different birds adapted to their environments
● Linnaeus’s classification scheme fit with Darwin’s theory of evolution
○ some organisms resembled each other more closely than others
○ Organized into “groups subordinate to groups”
Darwin’s arguments
1) Observation #1 - Members of a population often vary in their inherited traits
, 2) Observation #2 - All species can produce more offspring than their environment
can support, and many of these offspring fail to survive and reproduce
3) Inference #1 - Individuals whose inherited traits give them a higher probability of
surviving and reproducing in a given environment tend to leave more offspring
than other individuals
4) Inference #2 - This unequal ability of individuals to survive and reproduce will
lead to the accumulation of favorable traits in the population over generations.
Thomas Malthus
● Wrote an essay leading to Darwin’s proposal
● Thomas wrote: that much of disease, famine, suffering was the consequence of
the human’s population potential to increase faster than food supplies and other
resources.
● Darwin realised the capacity to overproduce was a characteristic of all species
Individual organisms cannot evolve as it is the population that evolves over time.
Natural selection favors Drug-resistant pathogens
● NS is process of editing not creative mechanism
● NS favors those characteristics in a genetically variable population providing
benefits to current environments/events
Fossil-Record in Evolutionary Patterns
● Documents patterns of evolution
● Origins of new groups and organisms
● Formation of new species and origin of major new group of mammals, the
cetaceans
Biographical Supports os NS
● Take into account continental drift
● Determine origin of species
● With endemic (found no where else in the world) we can see how organisms are
closely related adapted to their environments. Giving rise to new species
Homologous and Vestigial Structures
Homologous structures
● Represent variations on a structural theme that was present in their common
ancestors
● Develop into structures with very different functions
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller nkohoot. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $6.69. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79202 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now