Chapter two - Waleska Reyes

Chapter two - Waleska Reyes

Kolbert begins this chapter by discussing the idea of extinction and how to many people it wasn’t an obvious idea. Kolbert gives the example of Aristotle’s’ History of Animals that she believes it didn’t “ever considering the possibility that animals actually had a history”.

Kolbert explains that the idea of extinction began during the Renaissance when the word “fossil” was first used. During the Enlightenment, many people believed that rather than extinction animals simply evolved. I predict that during this chapter the theories of extinction versus evolution will be discussed.

Cuvier is introduced as the person who set in motion the idea that animals go extinct. The book emphasizes that Cuvier did not have any evidence to back up his theory, however, he believed that the fossils that were dug up as well as animal remains were enough proof to set the idea in motion. Cuvier can be connected to many Renaissance men that questioned common beliefs. For example the Heliocentric and Geocentric theories. Combative ideas in science have existed for centuries. Just like the Heliocentric theory was proven Cuvier's extinction idea became more realistic as more fossils began to be discovered.

This chapter relates greatly to the idea that thinking evolves over time. Furthermore the theme I related this chapter to is: science is a method of learning more about the world. With science, through digging up the fossils, Cuvier’s theory was proven to be true. Now due to this information, we are able to understand our planet’s history better.  

Chapter Seven (Sarah)

Coral reefs are important since many animals rely on them whether it be for protection or as a source of food. I didn't really know that coral reefs were that important since I don't normally here a lot about them, but they are an important ecosystem that is disappearing.

The chapter mentions Darwin's paradox which questions why coral reefs are rich in nutrients even though the waters they grow in aren't. It is interesting since it would make sense for coral reefs to reflect some of the same properties of the environment it grows in. The coral reefs could get the nutrients from somewhere else or maybe from other organisms since many do go to coral reefs.

Many organisms can be found in coral reefs whether it be in the coral itself or in the reef, they live there and rely on it. But due the ocean acidification it is dying which can badly hurt its ecosystem since many animals have learned to rely on it so without it, it may be hard for many animals to survive.

Chapter 2 by Andrea Guinanzaca

Chapter two covers how Kolbert studies the history of the concept of “extinction”. She first begins with the idea that everyone from the age of 4 had some sort of idea what extinction meant. She uses children as an example because children at an early age know that extinction exists because they know that dinosaurs once existed. The first historical figure that  Kolbert introduces is Aristotle, who wrote a long essay about animals went extinct. Later, she introduces Carl Linnaeus, a biologist who also supported the concept that animals go extinct. Later, the main historical figure that Kolbert focuses is on Georges Cuvier. He was a young man that studied fossils of different animals. The fossils he studied made him realize that the animal remains who once belonged to doesn't exist anymore. He also believed that animals go extinct, however, he didn’t know why and what were the reasons that caused animals to go extinct. So, therefore, there was no way for him to back up his idea. Throughout the chapter, we notice how evidence becomes an important strategy when trying to prove a scientific theory. In addition, Cuvier still continues to study further into his idea in order to make it a definite and robust theory. In order to do this, Cuvier took 2 steps in order to make this possible, he first continued to travel around the world, researched and studied more extinct species. Secondly, he shared his findings and ideas with the public. He took these two initiatives in order to prove his theory since it was controversial. Back then many believed that extinction existed but other did not; similar to how people think about extinction today. In the chapter, Kolbert description of Cuviers’ story shows how dedicated he was to prove his theory. Although he died, he was known for his scientific discoveries and became a popular and respected scientist.

An APES theme that can connect to this chapter is science is a process. According to the chapter, it states, “By the middle of the nineteenth century, many of [Georges Cuvier’s] ideas had been discredited. But the most recent discoveries have tended to support those very theories of his that were most thoroughly vilified, with the result that Cuvier's essentially tragic vision of earth history has come to seem pathetic.” This is because Cuvier’s story reflects how it takes days, months, years, decades, and even centuries for a theory to be supported in the science field.  Also, due to Cuvier's discoveries and proven theory, his idea eventually supported the term “fossil craze”. It was a term that made scientists realize that older fossils were buried deeper. Overall, the ideas that human activity creates destruction wasn’t mentioned in this chapter. This shows how scientists didn’t believe that human beings were responsible for the upcoming mass extinction. However, the idea changes as more scientific research are being done.

Chapter 1 by Andrea Guinanzaca

In this chapter, Kolbert also begins with a mysterious note which makes us ask “what happened to the golden frogs of El Valle?” She finds out that the golden frogs of El Valle in Venezuela have gone disappearing at faster rates. She reads a magazine that talks about these golden frogs, she also reads about how there are biologists that are trying to build a special facility for the golden frogs, a place which they call “frog hotel”. In this “frog hotel”, golden frogs are being kept there and fed well. After Kolbert reads the magazine, she decides to make a visit to El Valle Amphibian Conservation Center also known as “EVACC”. There she meets Edgardo Griffith, a man who spent most of his life studying different kinds of amphibians. Throughout this journey, Kolbert learns that the golden frogs aren't the only species that has been disappearing. There have been other frog species that have disappeared in the past years, not just one species but several at a time. The investigation of the disappearance of the golden frogs is later “justified” by an unidentified fungus called Batrachochytrium dendrobatidis, that has spread through different parts of South America. It is later noted that the fungus is probably the reason why golden frog populations have declined rapidly and why other frog species in different areas of the world have disappeared as well such as in Colombia, Australia, and New Zealand. Although Bd is the essential cause of why different frog species are becoming extinct, Kolbert notes that the only way for this fungus to have spread is due to human travel. An APES theme that this chapter can connect to is humans alter natural systems. This is because population growth enables humans to travel to different areas of the world without realizing their rate and scales impact their surrounding environment. In conclusion, Kolbert notices how humans can cause negative impacts to other living organisms by spreading unusual organisms to different parts of the world. In addition, she also realized that sometimes it isn’t our intention to create destruction because our real intention is to save species from extinction. She uses Griffith as an example, Griffith is trying to save different frog species but little does he know that they’d probably die in glass tanks. She says “... even if Griffith can save individual frogs from extinction, he can’t preserve their natural rainforest habitat.”

Prologue by Andrea Guinanzaca

In the Sixth Extinction, Kolbert begins the prologue by noting a mysterious species that has evolved throughout the years and spread around different parts of the world. Eventually, we realize that the species she was talking about is basically, us (humans). She establishes that the world is impacted by humans negatively and positively. The negative is that we can create destruction in the environment we live in such as hunting for animals that causes these animals to move to different areas and adjust to environments they aren't used to. However, humans also have positive impacts in this world because we accomplish remarkable achievements such as improving animal and human life with advanced technology and methods that allow living things to stay alive.

An APES theme that the prologue can connect to is that science is a process. This is because, in the prologue, Kolbert describes humankind as a species that develops over time. For example, in the chapter, Kolbert states, “The process continues, in fits and starts, for thousands of years, until the species, no longer so new, has spread to practically every corner of the globe… Homo sapiens… reproduce at an unprecedented rate. In a single century the population doubles; then it doubles again, and then again.”  In this quote, Kolbert talks about how humans coming into this world was a whole process. Later, towards the end of the prologue, Kolbert talks about how they were five past predecessors that lead the planet to undergo 5 mass extinctions. Overall, throughout this book, I believe that Kolbert will focus on proving the point that mass extinction is currently happening in our planet and that there are several ways we can do to delay or even stop it from happening.

Chapter Six (Sarah)

Due the increase of carbon dioxide in the atmosphere because of humans, the ocean is becoming more acidic. This is bad since it is hurting ecosystems and their biodiversity since it is killing many marine animals and plant. For example, the mytilus galloprovincialis is an adaptable, invasive species that cannot be found in acidic waters. Acidification has already played a part in a few mass extinctions so I wonder if it will play a part again since it seems like carbon dioxide levels will not drop any time soon so the ocean will become more acidic. Some species will be able to grow, but others will go extinct which can throw off the balance in the ocean since if a certain species dies they will not be able to keep another species in check.

Chapter Five (Sarah)

There are many hypotheses about mass extinction. One of the many that is talked about the most is how an asteroid killed the dinosaurs. The most interesting theory to me is the one about the Nemesis since it would be hard to image there was a "death star" that rains down comets every twenty- six million years. If there was, I wonder when the next mass extinction would happen and what animals and plants would go extinct.

In this chapter, Zalasiewicz describes rats as very adaptable sine they've survive for along time even in environments they didn't originate from. This makes me curious since in the previous chapter Taylor says that during a major extinction the rules of a specie's survival can change drastically. So, would there be a condition where rats would have a hard time surviving in and no longer be able to adapt in?

Chapter one - Waleska Reyes

Chapter one - Waleska Reyes

The first chapter of Elizabeth Kolbert’s “The Sixth Extinction”, starts off with a description of a Town in Panama called El Valle De Anton, which is in the center of a volcanic crater. The author, Kolbert, discusses that in the market of El Valle there are numerous amounts of golden-frog figurines. The golden frogs are found all over El Valle and are yellow with brown spots. It is also interesting to note that they are poisonous. Kolbert highlights that the golden frogs were very present in El Valle. As a result, many were alarmed when they began disappearing.

Many attempts were made to preserve the golden frogs by raising a few indoor, but these attempts did not seem effective. Kolbert was so intrigued by the occurrence she decided to visit The El Valle Amphibian Conservation Center (EVACC). Amongst many other frogs, Kolbert found a few dozen tanks of golden frogs. EVACC is described as a place in the middle of nowhere and therefore isolated from the rest of the world. Kolbert describes to the extent to which the golden frogs are being protected. Kolbert meets the director of EVACC, Edgardo Griffith, an individual who had devoted his entire life to amphibians. Griffith notes that golden frogs are not the only frogs disappearing, “we are losing all these amphibians before we even know that they exist” (pg. 10)  Griffith states. This quote made me question why it is that they are disappearing? Because when I think of destruction for the environment or any wildlife I think of humans. So are we killing off these species without knowing or is there something else out there?

Later on, Kolbert reveals that a fungus from chytrids, Bd for short, was what was killing the golden frogs. How do you get rid of a fungus that infects an entire rainforest? The answer is you can’t. The most daunting part is this fungus is spreading all over the world. After reading this passage I connected it most with the theme that science is a way of learning more about the world due to the fact that as previously stated there is so much we don’t know. Science allows us to investigate and ask the important questions we saw in this chapter.

Here is a video from a Quinoa farm/factory in Ecuador:

Frank Valoy- Chapter 13: The Thing with Feathers

             In chapter 13, Elizabeth Kolbert goes to the Institute for Conservation Research near the San Diego Zoo. Researcher Marly Houck showed Kolbert the remaining cells of the poʻouli, or black-faced honeycreeper, which were kept in a metal tank with liquid nitrogen. This place where Houck took Kolbert to see these cells was known as the “Frozen Zoo”.
             Later in the chapter, Kolbert begins to suggest that humans need to start taking action to prevent species from extinction because they dwell so much about the future, but they don’t focus on saving these species (Pg. 261). This connects to the theme “A suitable combination of conservation and development is required” because it’s been indicated that we need to try harder to find ways to preserve endangered species and prevent them from becoming extinct.
             Kolbert goes to a veterinary hospital near the institute and sees the Hawaiian crow named Kinohi. She saw that Barbara Durrant, the director of reproductive physiology, was trying to get Kinohi to ejaculate so she can take its sperm and impregnate another crow during breeding season. However, it wasn’t working. (Q) I wonder what Barbara will do if Kinohi still won’t be able to ejaculate.
             After this, Kolbert starts explaining the term “Sixth Extinction”. The term revolved around the idea of extreme changes in the environment because of humans. A quote that I found to be very interesting states, “Right now we are in the midst of the Sixth Extinction, this time caused solely by humanity’s transformation of the ecological landscape” (Pg. 267). (E) Based on this quote, humans are the cause of this extinction because they are dramatically changing the way of life for animals and plants, connecting to the theme “Humans alter natural systems”.
             At the end of Kolbert’s book, she starts to shift her focus point of extinct species to humans. While humans are hurting many species of animals and plants by altering the environment, she wonders if humans will ever be hurt by their own actions.

Frank Valoy- Chapter 12: The Madness Gene

             In chapter 12, Neanderthal bones were found in Neander Valley. Eventually, they were found all over Europe and the Middle East. Possible theories were made about the extinction of the Neanderthals such as there being a disease. After speculating, it was found that humans were the primary cause.
             Kolbert explains that modern humans first arrived in Europe 40,000 years ago and outcompeted the Neanderthals. (C) This can be connected to Darwin’s theory of evolution and how species that are most adapted to a specific environment will survive. Swedish biologist Svante Pääbo performed many projects that revolved around extracting DNA from bones of different species. His latest project involved extracting DNA from bones of the Neanderthal and comparing it to modern human DNA. He found that both of their DNA were similar, but the modern human DNA demonstrated a mutation that allowed them to have more of an advantage. More bones were found such as skulls that were much thicker than the skull of a modern human. Some believed that Neanderthals were very hairy and walked with a slouch.
             During the genome project, Pääbo got Neanderthal bones and extracted their DNA. He found that the DNA was most similar to Europeans and Asians. Then, Kolbert mentioned the theory about how all modern humans came from a small population in Africa and part of this population migrated around the globe towards the East and North. It was believed that modern humans encountered Neanderthals through this migration and the modern humans eventually replaced them.
            The Leipzig Zoo began performing live experiments with chimpanzees, apes, and orangutans. When Kolbert visited the zoo to see an experiment on an ape, she saw that the results of ape were compared to the results of kids who also participated in the experiment. It was noticed that the kids outscored the apes with reading social cues. It turns out that apes don’t usually work with each other.
            Kolbert began talking about how Neanderthals would migrate as well, but they’ll stop when they encountered the ocean. However, modern humans were able to simply travel across the ocean in ships. (P) Based on this finding, I predict that this demonstrates an advantage that modern humans had over Neanderthals because of the mutation in their DNA.
Pääbo performed another experiment where he extracted DNA from a 40,000-year-old finger bone that was found in Siberia. It was discovered that this bone neither belonged to a modern human nor a Neanderthal. It was from a new group of hominids called Denisovans. He found that humans actually interbred with Denisovans.
             A quote that I found significant stated, “A tiny set of genetic variations divides us from the Neanderthals, but that has made all the difference”(Pg. 258). (E) Kolbert is trying to say that modern humans were able to out-compete Neanderthals because of their DNA, demonstrating another example of how humans caused another species to go extinct. This connects to the theme “Humans have had an impact on the environment for millions of years” because modern humans were able to survive better than Neanderthals, causing the human-dominated Anthropocene era.

Neanderthal Fossils

Frank Valoy- Chapter 11: The Rhino Gets an Ultrasound

             In chapter 11, Elizabeth Kolbert goes to Cincinnati Zoo and she sees a Sumatran rhino named Suci. At the zoo, Dr. Terri Roth attempts to have Suci ovulate so she can become pregnant. However, when Roth gave Suci an ultrasound, no eggs were released and Kolbert noticed that Roth was not surprised. (P) Since Roth wasn’t surprised, I assumed that this has been an issue for a while.
             Then, Kolbert mentions that the Sumatran rhino species have been decreasing and a captive breeding program are attempting to preserve them. The program had difficulties trying to get the rhinos pregnant and some rhinos died because they weren’t being kept in the proper conditions. For instance, the rhinos in the program were being fed hay, but that’s not their usual diet.
             The next day, Kolbert visited Suci again and the zookeepers weighed her. She weighed 1,507 lbs. It was said that Suci weighed 70 lbs when she was born and that there is an advantage of being large in size. With this idea, Kolbert began talking about other large species in the past that have been extinct and she was wondering how they disappeared in such a short amount of time.
             Later on, Kolbert talks about when she went to Big Bone Lick, a park that displayed replicas of extinct species with a museum and a gift shop. At this park, she learned about the causes of the megafauna extinction and they followed a common theme. They all dealt with humans. It was also found out that the megafauna extinction happened in a sequence of pulses that corresponded to the sequence of human settlement. After mentioning this discovery, the last line of this chapter stated, “Though it might be nice to imagine there once was a time when man lived in harmony with nature, it’s not clear that he ever really did” (Pg. 235). (P) Based on this accusation, I believe that she’s right, unfortunately. Humans are the ones who’ve been polluting the air and the oceans. Humans have been the ones littering and using up so much land that the Earth has to offer. I hope there will be a way humans can live in harmony with nature, but I feel that this won’t be the case in the future. This quote relates to the theme “Humans have had an impact on the environment for millions of years” because Kolbert is suggesting that humans have always harmed the environment for their own personal gain, creating destruction that animals, plants, and insects must struggle through.

Dr. Terri Roth with Suci

Frank Valoy- Chapter 10: The New Pangaea

             Elizabeth Kolbert begins chapter 10 by saying that it’s best to take a bat census in winter because they’ll be hibernating. When doing this, Wildlife biologists noticed many bats were dead and covered in a white powder substance. It was noticed that more bats were dying because of this white substance and they found out that is was a cold-loving fungus called Psychrophile. 

             Kolbert brings up the discovery about fossils of the same species being found on different continents. As a result of this discovery, German meteorologist Alfred Wegener believed that all of the continents were once combined into one supercontinent called Pangaea. 

             After discussing this discovery, Kolbert goes back to the bat situation and she goes with Al Hicks to the Adirondacks mountains to record a bat census. In one of the shafts inside the mountain, they saw many bats with the white fungus on them. Hicks believed that this fungus kills them because it dehydrates them and it irritates them.

             Kolbert mentions that since every continent has species of plants and animals from other continents, there’s an interconnectedness between them. Although the continents are now separated, this connection between them is defined by the term “New Pangaea”. This relates to the theme “The Earth itself is one interconnected system” because every continent benefits from each other through trade and through the introduction of new species. The chapter connected this to the Columbian Exchange. 

             Kolbert then talks about her trip to the Aeolus Cave with Vermont official Scott Darling and Hicks. Once they arrived, they saw many dead bats on the cave floor and collected samples.

             Kolbert brings up the idea of invasive species and she mentions that science writer Alan Burdick called Homo sapiens “arguably the most successful invader in biological history” (Pg. 210). (E) When Burdick says this, I understand what he means. Throughout history, humans already dominated the environment by farming and domesticating animals. Once the Industrial Revolution came along, technology became more advanced and urbaner areas were created. Ever since, humans were able to successfully use nature and their surroundings to their advantage. It was said that invasive species can lead to new and more evolved species, meaning that it’ll take some time for the ecosystem to restabilize.

             Kolbert said that she began going back to the Aeolus cave yearly and she noticed that the bat population continued to decrease. Eventually, some bat species were declared endangered. It was found that the white fungus was able to spread from one bat to the other because they hibernated in clusters.

Frank Valoy- Chapter 9: Islands on Dry Lands

             Elizabeth Kolbert starts chapter 9 by talking about her trip to Reserve 1202 in the Brazilian state of Amazonas. She describes Reserve 1202 as an almost perfect square with 25 acres of trees surrounded by a “sea” of scrubs.
             This reserve represents the Biological Dynamics of Forest Fragments Project (BDFFP) founded by biologist Tom Lovejoy. Before this project, Brazilian officials gave money to ranchers to chop down trees and raise cows. Lovejoy had the idea that scientists should tell the ranchers what trees to chop down and he introduced this idea to these Brazilian officials. They agreed and the project was formed.
             Kolbert drove to Reserve 1202 with Mario Cohn-Haft. She learned that Cohn-Halt could identify different bird species based on their calls. He claimed that this was the best way to accurately know how many bird species are present in the reserve. It was noticed that deforestation will lead to a decrease in these bird species.
             Kolbert began talking about land-bridge islands and how they lack diversity because the land isn’t suitable for many species to live in. A small population of species in these islands could eventually lead to local extinction because not many species will be able to adapt to the environment, causing most of the population to be gone.
             Cohn-Haft and Kolbert went to Camp 41 and explored deeper in the forest where they saw many species of insects. On their way back to Camp 41, Kolbert saw army ants and she learned that many species like birds and butterflies depend on them for food. After seeing these ants, it was calculated that there are between 2 million and 7 million tropical insect species.
             Most of the findings of the BDFFP were the loss of species. It was said that since humans are changing the environment with cities and roads, animals that need to migrate in order to cope with climate change won’t be able to, connecting to the theme “Humans have had an impact on the environment for millions of years”. This connects to the theme because humans are altering the environment for their own benefit.
             (C) This chapter connects to chapter 8 because Silman suggested the idea that there is a need for more well-placed reserves in order to better preserve animals and plants and Reserve 1202 is an example of one.

Frank Valoy- Chapter 8: The Forest and the Trees

             In chapter 8, Elizabeth Kolbert, forest ecologist Miles Silman, and Silman’s students travel to Peru. In Peru, they visit Silman’s diverse plots of trees that contain 1,036 tree species in Manú National Park. Kolbert mentions a pattern called “Latitudinal Diversity Gradient” (LDG) and it means that the variety of life is more richest at lower altitudes than at the poles. This is what they experienced as they visited these plots. There were 4 theories mentioned as to why the tropics are so diverse. These are the following theories explaining why:

1. More generations of species can be produced in the tropics. 
2. The tropics allow for more isolation due to its stable temperature.
3. The tropics existed a long time ago, allowing more time for diversity.
4. The tropics contain a lot of competition amongst species, causing these species to become specialized.

             Each of Silman’s plots was 2.5 acres and they experienced different temperatures in each plot of trees. It was mentioned that trees respond to climate change by moving upslope. Kenneth Feely, Sliman’s post-doc, found that these trees move upslope 8 feet per year. He noticed that each tree species move at a different rate.
             Later in the chapter, it said that the global temperature of Earth was much lower a long time ago and that there was an ice age. It was believed that ice ages were initiated by small changes in Earth’s orbit, creating a cycle: as temperatures decrease, more ice builds up and as temperatures increase, the ice melts. Many animals and plants had to cope by migrating.
             After that, the chapter goes back to the present and Kolbert explains that the global temperature is increasing quickly and the animals and trees in Silman’s plots will have to adapt fast. The problem with this is that some species will be able to adapt, but some won’t.
            Rudi Cruz, one of Silman’s students, wanted to see a specific frog species called Rhinella Manu. Kolbert read earlier that the Chytrid fungus already reach Peru and she had a feeling that they won’t be able to find it because of that. It turns out she was right. This connects to the theme “Science constantly changes the way we understand the world” because, in chapter 1, Kolbert and other biologists didn’t understand why many frog species were becoming extinct. Now that they learned about the Chytrid fungus being the cause of their disappearances, Kolbert better understood why they couldn’t find the Rhinella Manu. (Q) I wonder if Silman knew about this fungus.
             Kolbert explains the species-area relationship (SAR), which is demonstrated by the formula S=cA^z. In this formula, the S represents the number of species, the A is the size of the area, and z are the constants that vary according to the region. This relationship states that the larger the area you sample, the greater number of species you will find. Using this formula, Johann Reinhold Forster was able to estimate the extinction risk posed by global warming.
             An idea was brought up toward the end of this chapter about global warming. It was said that some species will adapt to global warming better than others. Silman suggests that better policing and well-placed reserves will protect biodiversity.

Frank Valoy- Chapter 7: Dropping Acid

            In chapter 7, Kolbert goes to One Tree Island, an island that is surrounded by a coral reef, where she visited a research center. It was said that the reef was caused by a storm called “Cyclone Hamish”.
             Later in the chapter, she talks about the discovery of the Great Barrier Reef, which was first found by Captain James Cook. Lyell had a theory “that reefs grew from the rims of extinct underwater volcanoes”(Pg. 128). Darwin developed his own theory when he went to Moorea Island. He theorized that once this island sank away, its surrounding reef will be an atoll.
             It was explained that reefs support many marine species with protection and food. There was a belief that reefs won’t survive the Anthropocene. (E) I interpreted this as another negative consequence of today’s human-dominated era.
             Ken Caldera, an atmospheric scientist, experimented the effect of the ocean’s pH levels with the high abundance of carbon dioxide being released into the air. His experiment revolved around the low tides near One Tree Island. Along with other biologists in the research center, he collected water samples to see how calcification rates on the reef had changed.
Marine biologist Chris Langdon experimented on his hypothesis, which was that corals care about the saturation state of the ocean. After his experiment, he noticed the following relationship: the reef grew faster with a saturation rate of 5, but grew slower with a saturation rate of 2.
             It was found that the saturation rates of the ocean are decreasing as more carbon dioxide is being emitted into the air, meaning that reefs in the ocean are going to be growing slower. (E) This is a problem because the chapter then mentions that reefs are very diverse with many different marine species, meaning that ecosystems will be lost if there are no more reefs. It can be concluded that the rise of urbanization since the Industrial Revolution plays a major factor in the rise of pollution into the atmosphere, destroying our planet little by little. This connects to the theme “Technology and population growth have enabled humans to increase both the rate and scale of their impact on the environment”.
             Towards the end of chapter 7, Kolbert talks about how coral reefs reproduce asexually through mass spawning by “budding”. Researcher Selina Ward tested the effects of acidification on mass spawning and she found out that as saturation levels decrease, the fertilization rates of reefs decrease as well.

Frank Valoy- Chapter 6: The Sea Around Us

             Elizabeth Kolbert begins chapter 6 by talking about her experience in Ischia. In Ischia, she swam with biologists Jason Hall-Spencer and Maria to see vents on the ocean floor, which were caused by a volcanic eruption. They noticed carbon dioxide bubbles coming out of these vents.
             Kolbert mentions the Industrial Revolution being a time of urbanization where humans began to pollute the air by releasing greenhouse gases into the atmosphere. She explained that ever since then, the amount of pollution being released into the air has increased and that it’s expected to increase the global temperature between 3.5 to 7 degrees Fahrenheit, triggering world-altering events (Pg. 113). (R) This suggests that humans are slowly changing the Earth’s environment in many negative ways, connecting to the theme “Humans alter natural systems”. I feel that this part of the chapter is implying that us humans today must change our way of life so that we’re not the only ones benefiting.
             It was found out that many greenhouse gases being released into the air, especially carbon, are being absorbed by the ocean, making it more acidic. This affects many marine species and Hall-Spencer stated, “...They’ve [Marine species] just got to tolerate what’s happening outside, and so they get pushed beyond their limits” (Pg.116). (E) I found this quote very significant because many species suffer the consequences of humans’ actions and they have no choice but to.
             Hall-Spencer did an experiment where he observed different marine species from different locations away from the vents of the seafloor and near them. He noticed that he saw fewer species the closer he got to the vents, which have a pH of 7.8. It was concluded that the higher the acidity, the fewer species present in the ocean.
             Ulf Riebesell, a biological oceanographer, also concluded that the higher the ocean acidification, the lower the biodiversity. He also found out that smaller organisms such as plankton tend to survive this increase in acidity. Kolbert mentioned that this was a cause of the 2nd out the Big Five extinctions during both the end-Permian and end-Cretaceous eras. An increase acidity of the ocean is also creating holes in the shells of calcifiers.
             Overall, the message of chapter 6 is that the Anthropocene is a time where humans are dominating the environment and harming it with high levels of pollution, leaving a legacy of destruction.

Chapter Four (Sarah)

The theory that many species went extinct at one point in time due to a catastrophic event was brought to light by Walter and Luis Alvarez. They came to this conclusions due to the amount of missing fossils and since there were high levels of iridium in some of the rocks and clay that would have came from a asteroid. This theory was dismissed and ridiculed by many scientists and seen as a way to get attention. Something I noticed is that when scientists don't support a theory or idea they often see it as a joke and make fun of the theory and its supporters. Eventually, people started to believe and open up to the K-T theory which was interesting since they had believed Lyell's theory about a slow extinction for a long time.

At the end of the chapter, the author asks the question "How could a creature be adapted, either well or ill, for conditions it has never before encountered in its entire evolutionary history?"(page 90). I think it may mainly come down to luck. In many cases, the dinosaurs would have survived over most of the species that survived the asteroid if you go by natural selection, but dinosaurs died out by chance even though they seemed like they would have the highest chance of survival.

Journal Entry Eight(Chapter 8)-Ziomara Aguilar

.Global warming does not only threaten animals in cold climate but also animals in the tropics. In Peru, Kolbert meets with a scientist named Miles Silman. Silman is a professor who is a forest ecologist and studies tropical ecosystems in South America. In Peru, there is a large diversity of tree and animal species. One theory that suggests such diversity in the tropics is that "the evolutionary clock ticks faster." Animals reproduce faster leading to more genetic mutations that lead to more varieties of species. Another theory reasons that there is more diversity in tropical climates because they have a low-temperature fluctuation, therefore having mixed zones(tree tops, tree bases, etc). Each zone can have different lifeforms with different thermal tolerances. A third theory suggests that tropical ecosystems are diverse because they are older and have been able to become more diverse over time.
Silman keeps a record of the diversity of life at 17 different "tree plots". Him and his team record the average diameter of a tree, different life forms and other information of each tree plot. Silam has found that on average, the increased temperature of Peruvian forests has driven plants and animals higher up. Every species has evolved in some way to cope with the changes in temperature.
Scientists predict that during the next century, average world temperatures will increase considerably at a very fast rate. This poses a threat to life on earth as it is not clear which species will migrate north quickly enough to survive.

Journal Entry Seven(Chapter 7)-Ziomara Aguilar

Located at the tip of the Great Barrier Reef in Australia is One Tree Island. On the island, there is a research station affiliated with the University of Sydney. There, scientists study the chemical composition of nearby coral reefs. Since 1770, when the first Europeans found the Great Barrier Reef scientists know that coral reefs are part animal, vegetable, and mineral. A coral reef is largely composed of a calcium-rich structure. The grow by adding new life forms over time. Scientists estimate that by 2050 the Great Barrier Reef will have completely eroded.

At the research station, Kolbert meets Ken Caldeira, who is a scientist that research focuses on the impact of carbon dioxide on the ocean's pH. He also researched the chemical composition of forests as well as the recent changes in global temperature. During the late 1980s, evidence that CO2 can destroy coral reefs with the Biosphere project in Arizona. The biosphere project was a huge glass structure that was designed to be a self-sustainig ecosystem. The people who lived there go altitude sickness because the CO2 levels were too high. The high CO2 levels eroded the compositions of coral in the biosphere, at this point people believed that coral reefs were immune to changes in CO2 levels. Studies have recently shown that coral reefs significantly erode when CO2 levels rise. At the current rate of CO2 emission, the reefs are expected to disappear in the next half-century.
This chapter also relates to the theme that humans alter natural systems because they release CO2 too quickly and it harms the reefs.

Journal Entry Six(Chapter 6)-Ziomara Aguilar

Kolbert's next stop is a small island called Castillo Aragonese in the middle of the Tyrrhenian Sea that was formed millions of years ago due to the pressure between Eurasia and African tectonic plate, this can also cause the release of carbon dioxide gas. Kolbert comes here to investigate the carbon dioxide levels of the surrounding water. Here, she meets two marine biologists, Jason Hall-Spencer and Maria Cristina Buia. They take her scuba diving and show her bubbles rising from seafloor vents.  Near these vents, there is very little sea life. This is due to the high levels of carbon dioxide which has a negative impact on marine life. Since the Industrial Revolution, carbon dioxide levels have increased because of the fossil fuels burned from factories and because of all the trees that have been cut down. The increase of carbon dioxide means that there is an increase in the ocean's acidity.

Kolbert predicts that by the year 2050 the ocean will be 150% more acidic than it was in 1800. The increase of carbon dioxide emitting wents have eroded the shells of many sea creatures. Acidification is very dangerous as it deprives nutrients for large animals, interferes with photosynthesis and wipes out ecosystems.

The theme that connects is that humans alter natural systems. This is because humans have been emitting carbon dioxide too quickly and creatures cant adapt.

Chapter 3 (Sarah)

The main focus of this chapter are the great auks, which used to be known as the first penguin. The extinction of the great auks is important for two reasons. First, they were a common species that were easy to find but started to disappear and can no longer be found, and it also opened up a hole in Darwin's theory of natural selection. The great auks had a large populations, enough resources, and didn't have many predators to make them decrease at the rate that they did. The reason for this is because the extinction of the great auks was mainly due to humans and not the environment. Humans would hunt or just take parts of animals that they felt were useful without carng about the consequences. This showed that humans can have a major effect on a species and their survival. But this was never really questioned or looked into further. Species such as the Charles Island tortoise and the Steller's sea cow also went extinct because of the actions of humans but some of the scientists mentioned in the chapter never tried to help preserve the species but cared more about proving their theories and speculations about the environment rather than protecting it.

Limon Miah- Chapter 13 Journal

In the final chapter of, The Sixth Extinction, Kolbert visits the Institute for Conservation Research, located in San Diego. While at ICR, she witnesses the last genetic remains of several extinct species, one being the black-faced honeycreeper, a Hawaiian bird. Kolbert then goes onto question if humans can be forward- thinking in order to save the species on Earth rather than being totally destructive and mindlessly continue killing off species of animals/plants. Adding on, Kolbert makes a point that though humans have been destructive for thousands of years, they are trying to make progress in saving endangered species, whether it be through trying to make species reproduce more often, or even through passing laws such as the Endangered Species Act, which protects at danger species from going extinct. Thus posing the question, can humans successfully preserve the remaining amount of species left on earth? Kolbert concludes the book with the thought that despite it’s important to focus on how humans can ensure their survival to the future, it is more important to focus on saving the life on Earth first. Also, that no matter what humans do at this point, the Anthropocene era has already begun. Therefore, no matter what humans decide to do now, the sixth extinction will determine the way that life looks on earth in the future.

An APES theme that this chapter connects to is that human survival depends on developing practices that will achieve sustainable systems. (R) The world is at a point where it’s fragile and another small change can set the world off to a very dangerous standpoint. Humans have contributed to enough destruction, whether it be environmental destruction due to factors such as pollution and global warming or the increasingly decreasing species occurring daily. Therefore, it is time that humans use the progress that they’ve made up to the modern day in order to help sustain and preserve the earth and the species on it. Humans are the only species present that is capable of doing such work, and therefore it is their responsibility to take active action in making this change happen before it’s too late. In the chapter, Kolbert wrote about a quote that she saw in the hall of biodiversity at the American Museum of Natural History, it stated: “In pushing other species to extinction, humanity is busy sawing off the limb on which it perches” (pg. 268). Essentially, the inevitable reality is that humans have already destroyed the earth enough, adding more damage to it would be catastrophic. If human actions continue to be the way they have been for thousands of years, then rather than affecting other species, humans will begin to hurt themselves. If humans don't take responsibility for their actions then they will become the first species to recklessly walk into an extinction that they’ve created for themselves.