Readings

NewsBits 07- Laser-activated hunters and the Origins of CRISPR

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If you’ve ever wondered about weird animal organs, here’s your chance to satisfy your curiosity. Learn about 7 animal organs that humans don’t have here.

A woman in Nevada died of a bacterial infection that was shown to be resistant to all available antibiotics in the U.S.  Will the international community realize that something needs to be done or is it too late?

When it comes to intertidal prey, the impacts of coastal bears and raccoons seems to be redundant. Does this mean that in coastal areas where bears have been eliminated, raccoons could fully replace them,?

The story linking Yellowstone National Park and DNA testing is fascinating. You can find a good write-up here.

Why would the fear and hunting behavior of mice be located in the same part of the brain? Scientists have found a way to flip a switch in mice and turn them into hunters.

Another case of parthenogenesis happened with a zebra shark recently. This s not the first time that a female has gotten pregnant without male contact. This process has been observed in species before, including komodo dragons and copperheads. However, it is believed this is the first time a shark has switched from sexual reproduction to asexual reproduction. This particular shark had previously had babies with a male.

Want to learn more about CRISPR? Here’s your chance to understand it in the context of its origins and some of the scientists involved.

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NewsBits 06- Declining cheetahs, bird migrations, and a beneficial centrifuge

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Mucus is gross, right? Have you ever wondered if this “troublesome” substance has any advantages? This article investigates the advantages of snot.

One recent paper shows that cheetahs are declining in dramatic fashion. With a global population estimated at 7100 individuals, cheetahs are thought to occupy only 9% of their historical range. Not only are they threatened by range contraction, but also range fragmentation.

If you’re interested, you can find out here why a wild monkey tried to have sex with a deer. He even acted in an aggressive manner when other monkeys got close.

Bird migrations look to be well-timed with high levels of vegetation along the way. If this is true, what will be the impact of climate change on these stops? Will there still be food where the birds expect there to be food?

Why hasn’t nectar evolved to be really sweet? The answer will drive you batty. Read here.

The rusty patched bumblebee, Bombus affinis, became the first bee of any kind in the contiguous 48 states to be declared endangered. Its population had declined 87% in the last 20 years. You can read the U.S. Fish and Wildlife announcement here.

The Pioneer Cabin tree, a giant sequoia in California, fell as a result of heavy rains. It was carved out in 1880’s and instantly became a tourist attraction. See here.

And, finally, you can find out here how a researcher constructed a DIY centrifuge that will help developing countries.

NewsBits 05- Rare sand creatures, Thylacines, and killer cats

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Arabian sand cats, Felis margarita harrisoni, were seen by camera traps for the first time in ten years. One of six subspecies, this cat lives in desert environments. Beyond that, not much is known. Check out the article.

There’s a recent home-made video from South Australia that claims to show a Tasmanian tiger, or thylacine, alive and well. The only thing is is that these creatures were declared extinct in 1936. They were hunted to extinction, but it seems their genetic diversity was limited before they went extinct.

According to a recent study, that looked at the overall impact of invasive predators, found that feral cats have contributed to over 60 extinctions and threaten the most species overall (430). Check it out, and then keep your cat(s) inside.

On the other side of the spectrum, a group of researchers looked at the socioeconomic benefits of re-introducing cougars into the Eastern U.S. The models predict that if cougars successfully recolonize the area, then over 30 years, deer density and deer vehicle-collisions would be reduced by 22%. The total avoided costs in North Carolina alone over 30 years would be just over $30 million, according to the models.

Here’s a fascinating story about Peter and Rosemary Grant and their quest to find evolution in action. The Grant’s are well-known for studying finches in the Galapagos. After decades of studying these birds, they are now focused on looking for the genetic factors driving the adaptations.

We can all agree that there is little downside to taking a walk outside. There may even be benefits.

Want to learn more about the CRISPR-Cas9 technology? Here’s a nice introduction of how it works, and this article explains how it could be used in conservation.

Guns, Germs, and Steel/Collapse- Book Reviews

Diamond, Jared. 2005. Collapse. Penguin Group, New York. 525 pp.

Diamond, Jared. 1999. Guns, Germs, and Steel. W. W. Norton and Company, New York. 441 pp.


 

A major factor contributing to a society’s success or failure is its response to environmental problems. While some of these problems are determined geographically and escalate independently of human intervention, often people must make decisions during environmentally unstable times. How do these decisions affect a society as a whole? Is it possible for people to know they are making the right decisions? Jared Diamond addresses these questions in two of his books, Guns, Germs, and Steel and Collapse.

Diamond presents an excellent case for geographic determinism throughout Guns, Germs, and Steel. Some societies were blessed with an ideal location and climate which caused them to domesticate plants and animals faster and easier. For example, Cortes and Pizarro both had the advantage of technology that, according to Diamond, existed because they were both from a more suitable geographic location. However, Cortes and Pizarro were not successful just because they were from an environmentally friendly area. A determining factor in a society’s success is the ability to make decisions that will benefit future generations. These decisions may certainly be influenced by biogeography, but certain choices stand alone and can make or break a society. Diamond addresses this very issue in Collapse.

Humans respond to ecological problems in different ways. Some responses and decisions cause a society to flourish while others lead a society in a downward spiral toward disaster. Decisions such as these are usually based on a number of different factors. For example, leaders are influenced by personal beliefs, religious beliefs, and the population’s beliefs. In societies that do not have any form of central leadership, the people in the society are influenced by these same factors. Some people may feel strongly about long-term issues and others want to fix small problems immediately. Some leaders are concerned with their people’s happiness and well-being, yet others are selfish and greedy. As mentioned above, these decisions almost certainly affect biogeography. If a society chooses to clear forests to build houses, it may take into account how much wildlife would be destroyed in the process and how that action would affect the area as a whole. Another society clearing the land may not care about the loss of wildlife as long as it is benefited financially from the houses. This is just one example of how decision-making is often determined by a society’s priorities.

Guns, Germs, and Steel explains the events that unfolded at Cajamarca in 1532 (Diamond 1999). This event clearly shows how decisions benefited a society. The Spaniards, being so close to the Fertile Crescent, had advantages because they benefited from food surpluses, domesticated plants and animals, and were writing by this time. This was only possible because of decisions made by the early Europeans (Diamond 1999). Pizarro took advantage of the technology afforded to Spain. Pizarro and the rest of the Spaniards had steel swords, lances, daggers, armor, a few guns, and horses – technological developments that enabled them to defeat the Incas. The Europeans could have responded to the environment in ways that would have harmed the society, but instead they had a vision in mind for the future. It was not that the Incas made bad decisions; they just did not have the opportunities that the Spaniards had. This ties in nicely with Diamond’s point that biogeographical factors are already determined for a society.

Diamond states five factors that contribute to a society’s downfall in Collapse. The first four factors that could contribute are environmental damage, climate change, hostile neighbors, and friendly trade partners (Diamond 2005). According to Diamond, the last factor – a society’s response to environmental problems – always plays a role (Diamond 2005). These first four factors are sometimes out of a society’s control. The Incas did not have a clue that the Spaniards would come and not be friendly. The Anasazi people had no idea that their climate would change. The Easter Islanders could not have predicted that having no trees would be detrimental. How a society deals with environmental damage, climate change, hostile neighbors, or friendly trade partners always proves significant. These responses could then cause one or all of the remaining factors. For example, if a society is experiencing a shortage of trees (environmental problem) and decides to do nothing about it, the climate could be altered and friendly trade partners could turn into hostile neighbors. If this particular society decides to do something about the shortage of trees, the climate may not change and once hostile neighbors could become friendly. This sounds like a simple concept, but these responses must sometimes be quick and well thought out to be successful.

All societies and the individuals that comprise these societies have certain core values that they consider to be important parts of their decision-making process. These core values may include religious beliefs or convictions, traditional opinions, or cultural beliefs. These three are often blended together. On page 409-410 of Collapse, Diamond explains this as “the challenge of deciding which of a society’s deeply held core values are compatible with the society’s survival, and which ones instead have to be given up.”

The Vikings in Greenland clearly show what happens to a society when poor choices are made. A series of mistakes led to the downfall and eventual collapse of their society. The Vikings started raiding other countries in AD 793, which led to an accumulation of wealth (Diamond 2005). When Eric the Red landed in Greenland in the AD 980’s, he found a land with a mild climate and green landscape; however, in time the Vikings destroyed the environment. As soon as they arrived they began clearing forests and causing soil erosion. They also stripped massive amounts of turf to insulate their houses (Diamond 2005). The Vikings also brought cows and sheep with them from Europe, but they soon found that the cows could not survive the cold weather. When times got tough, they went hungry because they refused to eat fish, an abundant food source in Greenland (Diamond 2005). The Vikings failed to learn from the native Inuit living on the island. A friendship with the Inuit could have led to a friendly trading system with the Inuit. They could have learned how to build long canoes to hunt and kill fish, seals, and whales. The Inuit may have taught them to use blubber as a fuel source. The Vikings did not understand which core values to abandon to survive in Greenland. They were a proud people who valued independent living. This pride turned into stubbornness and ended up blinding them. The Vikings were unable to make choices that would lead their society to success.

The parallels of the modern condition of Australia and the past failures of Greenland are striking. Australia is currently using some of its resources faster than they can be replaced. In Collapse Diamond states, “At present rates, Australia’s forests and fisheries will disappear long before its coal and iron reserves, which is ironic in view of the fact that the former are renewable but the latter are not.” Just like the Vikings in Greenland, this situation seems illogical. The people in Australia continue to destroy the environment when they are already the most unproductive continent. Diamond states that the soils in Australia have the lowest nutrient levels on average which leads to the lowest plant growth rates (Diamond 2005). To be fair, Australia is unfortunate in that the climate is undesirable and rainfall levels are very low. However, bad choices led to today’s low productivity.

The British settled Australia so that they could have a place to put all of the jailed, impoverished people. They were afraid that these people would rebel if they were kept close to Britain. The British were only concerned about themselves, as were the Vikings; neither of these groups cared about the future of the islands they were settling. The British also introduced rabbits and foxes into Australia, which still causes problems today with the vegetation. They, like the Vikings, were too concerned with making this new place seem more like their native land. They introduced species that did not belong, and the Australians are still fighting the effects of these bad decisions.

Even though biogeography plays a part in the advancements and failures of societies, human decisions also play a significant role. Long-term vision is the key to establishing a healthy society that will thrive. Societies must be willing to let go of old habits if it is in the interest of future generations. The histories of the Vikings in Greenland and the British in Australia show what happens when societies hold on to core values and familiar habits. There are similar patterns developing in the U.S. Exotic species, global warming, fertilizer and chemical runoff are just a few examples of environmental problems. Educational programs must be organized so that people will recognize these problems and make decisions that will influence the future environment in a positive light. Adults need to recognize examples of past failures so that the same mistakes are not repeated. Parents must share these concerns with their children. Apathy, ignorance and stubbornness can and will ruin this country if environmental problems are not taken seriously.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NewsBits 04- Parasite conservation and humming-not-bird migration

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E.O. Wilson has a new book out, and it’s really good. You should read it. As a matter of fact, you should read all of his books. In this particular one, he says that we should set aside half of the planet to conserve biodiversity. You can read a review here.

So, maybe wolves in Yellowstone haven’t yet shown to influence, or scare, the elk population the way they were supposed to. However, maybe there is still such a thing as a landscape of fear. Ed Yong delves into this issue in a recent article, which describes a study done with raccoons.

Have you ever wondered what giant ground sloth burrows look like? If you have, then you’re in luck. The folks from Twilight Beasts wrote about them here. No one is quite sure what these tunnels were used for. Maybe for hiding. Maybe for mating.

Do you see anything strange about this “hummingbird”?
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The blind cavefish Cryptotora thamicola has been shown to climb waterfalls with a pelvic girdle similar to a salamander. You can see an interactive model of the pelvis here.

Here are some stunning camera trap images.

Tiny hominids, Homo floresiensis, vanished around 50,000 years ago. This is 40,000 years earlier than previously thought. Could it also mean that they disappeared because Homo sapiens appeared in the region during this same time? see the story here.

Carl Zimmer sits down with Job Dekker to discuss the shape of DNA. There are some really cool animations and applications in this video.

Birds have feathers, but there used to be other animals with feathers. Read about the evolutionary legacy of dinosaurs in today’s birds.

In his latest column, Carl Zimmer wonders if we shouldn’t let parasites and endangered animals continue to live together. He gives an interesting evolutionary perspective to conservation.