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Printable Handouts
Navigable Slide Index
- Introduction
- Outline (1)
- Biogeography
- Understanding biodiversity
- Patterns
- How it all began (1)
- How it all began (2)
- Species diversity is not evenly distributed
- Differences in tree diversity of forests
- Disjunct distributions
- Processes (1)
- Rivers, mountains, deserts, etc., can be barriers to some, bridges to others
- Processes (2)
- Plate tectonics
- How can we discern between dispersal and vicariance?
- Dating the phylogenies is a crucial step
- Other cases of long-distance dispersal
- Reconstructing ancestral ranges is also key
- Problems in inferring ancestral ranges from extant distributions (1)
- Problems in inferring ancestral ranges from extant distributions (2)
- Dispersal, vicariance & duplication in relation to speciation process
- Dispersal-driven biogeography: island biogeography
- Species-area relationship
- Island-dependent diversification of Caribbean lizards
- Outline (2)
- South America
- The Neotropics
- Neotropical biomes
- Most species are found in the Neotropics
- …but this diversity is not distributed evenly
- What about other groups? Fishes...
- Diversity of fish
- Outline (3)
- Main data sources in biogeography
- Species occurrences – a revolution
- Biases
- Errors
- “We are drowning in information, while starving for wisdom”
- Outline (4)
- A few (!) methods related to biogeography
- Inference of ancestral areas using phylogenies
- Defining areas using network theory
- Fossil biogeography
- Outline (5)
- Example #1 – Connecting the Americas
- Isthmus of Panama
- Impact on thermohaline circulation
- The Great American Biotic Interchange
- The interchange may have occurred earlier than previously thought
- Example #2 – Teasing apart the drivers of speciation
- Teasing apart the drivers of speciation using molecular phylogeny
- Example #3 – The assembly of neotropical diversity
- Example: angiosperms
- Results: direction of dispersals
- Results per major clades
- Biome conservatism vs. biome shifts
- Summary
- Thank you
Topics Covered
- Biogeography
- Biodiversity
- Species distribution
- Ecology
- Fossil records
- Data collection
- Speciation
Talk Citation
Antonelli, A. (2021, March 30). Biogeography: explaining the geographical distribution of organisms [Video file]. In The Biomedical & Life Sciences Collection, Henry Stewart Talks. Retrieved December 3, 2024, from https://doi.org/10.69645/SJGE7141.Export Citation (RIS)
Publication History
Financial Disclosures
- Prof. Alexandre Antonelli has not informed HSTalks of any commercial/financial relationship that it is appropriate to disclose.
Transcript
Please wait while the transcript is being prepared...
0:00
Hello and welcome to this lecture on one of the most fascinating,
fundamental and integrative topics in biology:
biogeography, the geography of life.
Have you ever wondered why there are no penguins in the Arctic,
no kangaroos in North America,
and why all (but one) species of cacti are naturally confined to the Americas?
These are just some of the questions that biogeography tries to answer.
My name is Alexandre Antonelli but most people call me Alex.
I'm a professor of biodiversity and
systematics at the University of Gothenburg in Sweden,
and Director of Science at the Royal Botanical Gardens in the UK.
0:42
I've divided this lecture into five parts.
First, I'll introduce you to biogeography,
what it means and what the major components of it are.
I'll then showcase the rich diversity in the American tropics,
also called the 'neotropics',
which is my main area of research
and where many important questions remain to be answered.
To answer those questions,
I'll mention the main sources of data that I
needed and some of the methods to handle such data.
Finally, I'll give you some examples from my own research group,
which I hope will inspire you to one day also become a biogeographer.
Just so you know, I'll be asking
a few questions throughout this talk that I want you to think about.
I'll let you know when you should pause
the presentation, so you can think about the answers before moving on.
1:32
There are several definitions of biogeography,
but the one that I like the most is:
"The science that attempts to document and
understand the spatial patterns of biological diversity."
It's a very broad but correct definition,
which also means that many other topics in biology
like taxonomy, systematics, population genetics, can
all be regarded within this framework or at least as contributing to it.
In other words, this is all about understanding biodiversity,