Summary
Summary 3. Biodiversity and Conservation
- Course
- Institution
- Book
Chapter 3 for the ESS IB syllabus. The notes are in great detail and basically replace the book.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
More summaries for
-
IB ESS COMPLETE STUDY GUIDE
-
4. water and aquatic food production systems and societies
Seller
Followivanstanisavljevic
Reviews received
Content preview
3. Biodiversity and ConservationBiodiversity
Biodiversity: is the variety of all life forms on earth
o Species diversity: number of species and abundance of earth species that live
in a particular location
o Habitat diversity: range of different habitats in an ecosystem
o Vegetative diversity: Number of different species of vegetation present
o Genetic Diversity: range of genetic material present in a population of species
Diversity indices: the way communities can be described and compared
N (N −1)
o Simpson’s Diversity Index: D=
n(n−1)
o N= total number of species
o n= number of individual species
Factors biodiversity is dependent on:
o Diversity changes through succession
o Greater habitat diversity-> greater species and genetic diversity
o Complex ecosystem= stability
o Human activities often simplify ecosystems
o Human activities modify succession through burning, grazing
Hotspots: region with level of biodiversity that is under threat from human activities,
they tend to…:
o Be nearer to the tropics-> fewer limiting factors
o Have larger densities of human habitation nearby
o Cover 2.3% of land surface
o Habitat contains more than 1 5000 species of plants which are endemic
(species that only exist in a certain geographical area)
Natural selection: those more adapted to their environment have an advantage and
flourish and reproduce
, Speciation: change of a species over a long time
o When a population of a species separate and cannot interbreed
o Environment they inhabit changes and new species form (geographical or
reproductive causes)
> Physical barriers: species can develop into new ones is separated by
mountain range or oceans- it will split the gene pool (large flightless
birds only exist in continents once part of Gondwana)
> Land bridges: allow species to invade other areas (e.g. North and South
America) for example: bears from N to S America- Bridge: Central
America
> Continental drift: continents moved to new climate zones
o Changing climatic conditions- food supply changes: forces
species to adapt and results in increase of biodiversity
o Diverge: create physical separation
o Converge:
-move together, thus creates mountains: physical Barriers
-collide and one plate id under the other: subduction zone,
volcanic chains formed, land bridges
Similar groups of animals: llamas and camels are distant cousins; African and Indian
elephants suggest continents used to be connected in the past
Mass extinction: 5 major ones due to: rapid change of climate, natural disaster
(volcanic eruption, meteorite impact) now: Holocene extinction
Mass extinction MYA (million Geological period Est. of losses
years ago)
th
6 Now Holocene Unknown
5th 65 Cretaceous 17% families and
all large animals
th
4 199-214 End Triassic 23% animals,
some vertebrates
rd
3 251 Permian Triassic 95% of all species,
54% families
2nd 364 Devonian 19% of all families
st
1 440 Ordovician 25% of all families
Current mass extinction caused by humans over few decades
> Cities, roads, industries
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 ivanstanisavljevic. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.40. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
82871 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now