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Last night's Science Under the Stars lecture was "There is More to the Tropics than Rainforest: Introducing Brazil's Neotropical Savannah" by grad student Mariana Vasconcellos.
What she most wanted us to know was that Brazil has a big, awesome savannah and that Alfred Wallace is the founder of biogeography, which is a fascinating field.
The Cerrado savannah
There are hotspots of biodiversity and Brazil's Cerrado is one of the top twenty-five hotspots in the world and the only one that's a savannah. A savannah is a grassland; there can be trees and bushes, but the canopy is not dense (except along creeks and rivers), so the sunlight can get through to the grass.
The Cerrado comprises 1/4 of Brazil. "Cerrado" means cerrated, which is the shape of the rocky land. That means where there are rivers, there are waterfalls.
There are two seasons: the rainy (during our winter) and the dry (during our summer). The temperature averages 25 degrees C all year round.
The life forms
The Cerrado has 10,000 species of plants, 45% of which are unique to that area. Of the lizards, 45% are unique, and 30% of the frogs and snakes are unique.
So it's pretty alien. Even if you're familiar with the African savannah, the Cerrado will seem alien. For one thing, there are no roving herds of large herbivores. That means no elephants, zebras, giraffes, or lions. The main herbivores are insects.
There used to be many large ungulates, but they are exctinct. (She showed pictures; they did not look familiar.) They do have large cats--they eat deer and small mammals.
When South America slammed into North America so long ago, life on the two landmasses had been evolving independently for a very long time. Pumas, tapirs, and deer migrated south from North America during the ensuing "Great American Interchange."
Mariana studies treefrogs. Their main predators are snakes, but she's also seen birds and monkeys eating them.
I couldn't find the video she showed us, but this one is just about as good (too many humans). It shows that my words are a pathetic description of this area.
Biogeography
The two main questions biogeographers ask are:
1) Why are certain species in some habitats but not others?
2) Why do some areas have more species than others?
The Cerrado has many different landscapes, so that can support multiple species. But also, life is difficult, so life has moved in many directions to find ways to adapt. Here are some of the difficulties:
* the groundwater is very deep
* the soil is nutrient poor
* the soil has toxic levels of aluminum
* drought
* fires
So you have plants with very long roots to reach the water table and thick bark to protect them from fire. The fires tend to be due to lightning strikes at the end of the dry season; this is immediately followed by the rainy season, so new life can get a foothold quickly.
Mariana has learned that the Cerrado treefrogs she has studied are generally more closely related to a rainforest treefrog than to another savannah treefrog.
Alfred Wallace worked with Darwin on the theory of evolution and he is the one who named this region the neotropical savannah. "Neo" is because it's in the new world.
Depressing environmental news
Nowadays you can't hear about cool nature things without also having to learn that it's all disappearing--in this case to farmers. Only 3% is currently protect by law. At the current rate, it will all be gone in thirty years.
Random book recommendations
Before the talk, I overheard some other people talking to each other and recommending books. They were all in the helping professions (or studying to join them.)
One was The New Jim Crow. Want to guess what that's about? I'll give you a second.
The other was A Million Pieces, a mostly true book, which was represented as totally true until after the author spoke on Oprah Winfrey's show, and boy was she angry when she found out after having recommended this book.
I don't know what that book's about, I'm guessing someone's road to recovery. The first one is about prisons.
Old colleagues
I saw one of the professors I used to type for and he recognized me. He said it's been a long time. Twice. He actually looks good. He aged rather quickly while he was Chair, but apparently not much at all since then.
I learned that the whole time he was Chair, he was fighting for grad students not to have to pay tuition, at least in biology where they do the bulk of the research work.
What she most wanted us to know was that Brazil has a big, awesome savannah and that Alfred Wallace is the founder of biogeography, which is a fascinating field.
The Cerrado savannah
There are hotspots of biodiversity and Brazil's Cerrado is one of the top twenty-five hotspots in the world and the only one that's a savannah. A savannah is a grassland; there can be trees and bushes, but the canopy is not dense (except along creeks and rivers), so the sunlight can get through to the grass.
The Cerrado comprises 1/4 of Brazil. "Cerrado" means cerrated, which is the shape of the rocky land. That means where there are rivers, there are waterfalls.
There are two seasons: the rainy (during our winter) and the dry (during our summer). The temperature averages 25 degrees C all year round.
The life forms
The Cerrado has 10,000 species of plants, 45% of which are unique to that area. Of the lizards, 45% are unique, and 30% of the frogs and snakes are unique.
So it's pretty alien. Even if you're familiar with the African savannah, the Cerrado will seem alien. For one thing, there are no roving herds of large herbivores. That means no elephants, zebras, giraffes, or lions. The main herbivores are insects.
There used to be many large ungulates, but they are exctinct. (She showed pictures; they did not look familiar.) They do have large cats--they eat deer and small mammals.
When South America slammed into North America so long ago, life on the two landmasses had been evolving independently for a very long time. Pumas, tapirs, and deer migrated south from North America during the ensuing "Great American Interchange."
Mariana studies treefrogs. Their main predators are snakes, but she's also seen birds and monkeys eating them.
I couldn't find the video she showed us, but this one is just about as good (too many humans). It shows that my words are a pathetic description of this area.
Biogeography
The two main questions biogeographers ask are:
1) Why are certain species in some habitats but not others?
2) Why do some areas have more species than others?
The Cerrado has many different landscapes, so that can support multiple species. But also, life is difficult, so life has moved in many directions to find ways to adapt. Here are some of the difficulties:
* the groundwater is very deep
* the soil is nutrient poor
* the soil has toxic levels of aluminum
* drought
* fires
So you have plants with very long roots to reach the water table and thick bark to protect them from fire. The fires tend to be due to lightning strikes at the end of the dry season; this is immediately followed by the rainy season, so new life can get a foothold quickly.
Mariana has learned that the Cerrado treefrogs she has studied are generally more closely related to a rainforest treefrog than to another savannah treefrog.
Alfred Wallace worked with Darwin on the theory of evolution and he is the one who named this region the neotropical savannah. "Neo" is because it's in the new world.
Depressing environmental news
Nowadays you can't hear about cool nature things without also having to learn that it's all disappearing--in this case to farmers. Only 3% is currently protect by law. At the current rate, it will all be gone in thirty years.
Random book recommendations
Before the talk, I overheard some other people talking to each other and recommending books. They were all in the helping professions (or studying to join them.)
One was The New Jim Crow. Want to guess what that's about? I'll give you a second.
The other was A Million Pieces, a mostly true book, which was represented as totally true until after the author spoke on Oprah Winfrey's show, and boy was she angry when she found out after having recommended this book.
I don't know what that book's about, I'm guessing someone's road to recovery. The first one is about prisons.
Old colleagues
I saw one of the professors I used to type for and he recognized me. He said it's been a long time. Twice. He actually looks good. He aged rather quickly while he was Chair, but apparently not much at all since then.
I learned that the whole time he was Chair, he was fighting for grad students not to have to pay tuition, at least in biology where they do the bulk of the research work.