Final Thoughts on Natural Security

To me this book had great insight into the natural world and really tied together concepts and ideas that were relevant to our human world. It highlights the ideas that there "is no one natural solution to security problems we have", and that the main mechanisms we can use to better ourselves is to adapt, anticipate, and be economically conscious of the decision and tactics we are using (pg 10). Overall the book was extremely interesting in the ways it attacked the every day security questions we have, from physical threats all the way to environmental and diseases threats. 

As I stated in my last blog post one of the most interesting chapters to me, that in my eyes, captured some of the main ideas we need to be aware of were the fourteen rules that were laid out in chapter 10 , Fourteen Security Lessons from Antipredator Behavior, by Daniel T. Blumstein. These rules covered the vast majority of important detailed concepts throughout the book, the rules were laid out like this:

• avoiding all risk is impossible
• overestimating risk is a good strategy
• it's possible to reduce risk by limiting exposure or being very careful when in risky areas
• detection signaling is a good idea and may reduce predation risk by encouraging the predator to select another target
• individuals should signal when they are in a safe position 
• exaltations are common
• important to assess signaler reliability 
• there can be qualitatively different responses to the same situation or problem
• reducing uncertainty by predator inspection is important to reduce costly responses
• adaptive to reduce defenses when risk decreases
• generalize defenses that work against more than a single threat
• unless there are great costs to maintaining a defense in the absence of a specific predator, it may be a good idea to keep all defenses up
• often expect habituation when there are many false alarms
• maintaining flexible responses is often a good idea

Each of these ideas, although applied to the natural world, can be directly correlated with our way of life and defense. whether it is to the physical threat of attacks or biological. 

Another key thing to realize about this book is that it truly does attack a lot of the main ideas that we have learned in this class; things like adaptation, weighing costs and benefits for evolving, and the idea that evolution can occur on several different levels. One of the most important ideas that I noticed was of adaptation. There were several accounts where adaptation was the main argument for how to fix things, whether that be adapting from our own mistakes or misfortunes or learning from other peoples as well. One of the most convincing quotes that I personally liked was when they said "security must ultimately come through adaptation" (pg 28). This essentially sums up one of the main arguments in my eyes.

To continue the overview of the book you would have to point out that it also uses numerous accounts of articles that aren't as biologically or scientifically related, but more politically influenced, or by other fields as well. These parts gave great background and insight into how other peoples ideas and thoughts on the subject are proposed, and thus offers a great opportunity to mesh the ideas together and possibly formulate a better way of going about national security. 

Life Ascending - Week 5: Final Thoughts

Life Ascending was a great choice of book. When I initially picked it I was intrigued about what it could possibly talk about and how it could possibly summarize the "greatest" inventions with just ten.  After reading it, I can say, it certainly convinced me and had me very caught into the book. The reason this happened was because of how the book was written and how Lane presented each new 'invention'; he explained and elaborated on each intention from a unique point-of-view - meaning he used interesting metaphor and always showed the 'invention' in both wildlife and humans. Had he just explained each 'invention', the book would have been boring, but thankfully he didn't.

For this last blog post, I want to focus on the last chapter of the book: Death. The reason I am doing this is well, its the last chapter of the book and the last post, so it feels appropriate. But, also because I found this chapter to be really interesting. When I firsts started reading this chapter I didn't know how death could be a beneficial invention; I could only think of the amount of pain that death causes both humans and animals. However, Lane convinced me otherwise, not that it doesn't cause pain because it does, but that it is incredibly beneficial. The quote that sold me on that ideas was this:

"Only death makes multicellular life possible. And, of course, without death there could be no evolution; without differential survival, natural selection comes to nothing"

I feel the quote is pretty self-explanatory. Death allows evolution to happen by survival of the fittest - the beneficial evolutions thrive, while the deleterious ones die. If deleterious evolutions did not die then there would be no moving forward with life. Just like with natural selection, if there was no death then everyone would have the same fitness and we could not more forward to more fit individuals. To me this is in fact one of the GREATEST evolution, ignoring that fact that death in every other ways sucks. I would have never thought of death this way and am so grateful to be able to this of it this way, there is more than just a negative meaning to the definition of death now.

Just like with the topic of death, after this book I so happy I can now explain all these evolution and have more the say about them, other that the basic common knowledge.

Week 5: Bittersweet Endings

Interestingly, I really like the later chapters of this book. They are not prescriptive but descriptive; in the latter chapters the authors focus on describing the political and social issues that disrupt peace and threaten security while simultaneously providing evolutionary explanations for these phenomena. However, they seldom attempt to suggest black and white answers tied to natural selection and evolution.

My favorite chapter: 

In Chapter 9: The Power of Moral Belief, Scott Atran explains how economic decision making  based on cost-benefit analyses is very different from behavior motivated by morals and sacred values. He states that current conflict resolution strategies assume that adversaries make rational choices but that his research indicates that what is considered to be rational behavior changes from one cultural framework to another and that some of the values and motivations intrinsic to a deep-rooted cultural framework cannot be translated or understood in the framework of other cultures. His team also found that "emotional outrage and support for violent opposition to compromise over sacred values is (1) not mitigated by offering material incentives to compromise but (2) is decreased when the adversary makes materially irrelevant compromises over his own sacred values" (pp.142) and that when people (for whom a terrorist group claims to be working for the sake of) foresaw the loss of a sacred value in exchange for materialistic gains they were less supportive of violence and were less likely to feel joy if they heard of suicide attacks. 

I am shocked by these findings. They are intuitive and make sense but at the same time, I never thought that the whole "dealing with terrorists" dynamic could be synthesized so relatively simply and accurately. 

I think the transition from prescriptive analyses to descriptive depictions is exemplified in the fourteen rules that Daniel T. Blumstein identifies in his essay Fourteen Security Lessons from Antipredator Behavior, i.e. Chapter 10. These rules also summarize the ideological evolution of the essays as the book progresses.

1) Avoiding all risk is impossible.

2) Overestimating risk is a good strategy in many circumstances.

3) It is possible to reduce risk by limiting exposure or by being very careful when in risky areas.

4) Detection signaling is a good idea and may, in some circumstances, reduce predation risk by encouraging the predator to select another target.

5) Individuals should signal when they are in a relatively safe position: flee to safety  then signal.

6) Exaptations are common.

7) It is very important to assess signaler reliability and to behave accordingly

8) There can be qualitatively different responses to the same situation or problems

9) Reducing uncertainty by predator inspection is an important way to reduce costly response.

10) Reduce defenses when risk decreases

11) Have generalizable defenses that work against more than a single threat. 

12) Unless there are great costs to maintaining a defense in the absence of a specific predator, it may be a good idea to maintain all defenses. 

13) We should often expect habituation when there are many false alarms.

14) Maintaining flexible responses is often a good idea. 

 Although a few of these rules are definite, most of them leave room to develop variations of the ideal strategies provided in earlier chapters. I think that these generalizable rules are more feasible for policy makers to implement and for governments to improve on their national security management. 

I would definitely recommend this book to a friend but I would warn them that enjoying this book is similar to consciously working on developing an acquired taste. 

Week 5: Paleofantasy

Overall I really enjoyed this book. It was very interesting and Zuk brought up some really strong points in her argument that we as humans are still evolving and at a faster rate than we would think. Her last sentence of the book says it all. "But change is continuous, and those ancient ancestors encountered changes as well; they domesticated animals, they grew crops, and they dealt with diseases. Change does not have to mean disaster. Sometimes it just creates more change" (Zuk, 271). I think what she means by that last part, is that changing and adapting happens as a species evolves over time. We don't really look at it as "good changes" or "bad changes" but instead at how they evolve to adjust to other factors. Another big theme in the book was Zuk proving that the paleo-diet isn't as effective as the media says it is. The paleo-diet pushes us to eat the same way as our ancestors since it is "more natural" and it is what we grew up with and that our bodies can't take the new processed foods we eat now. Zuk proved that theory to be false time and time again throughout the book which allowed her to keep linking back her arguments to the title of the book "Paleofantasy".

Your Inner Fish- Week 5

As I finish reading Your Inner Fish, I am happy to say that I have learned a lot that I hadn't known before. Shubin did a wonderful job in explaining the many relationships that humans share with other organisms. He was able to make these evolutionary connections throughout the entire book and really engaged the reader in wanting to learn more. He provided evidence about these evolutionary viewpoints by talking about the structure of the human body and the many aspects of it that were similar to other life forms. His writing style also made the concepts introduced easier to follow. Overall I definitely enjoyed reading this book. I was intrigued by all of the evidence that Shubin provided and his writing style definitely got me wanting to read more. Shubin's writing style made it possible for me to make connections to other concepts that I had learned before. The author did a phenomenal job in explaining how parts of the human body are in fact similar to those of other organisms that, structurally, look nothing like us. This book made me realize how connected we actually are to other organisms and that our DNA, cells, and organs are the evidence to all of these connections. 

My Girlfriend's Boyfriend?

Subscribers of the paleo-lifestyle use the "we are adapted to caveman life, therefore we should live more like cavemen" argument to advocate more than just eating like cavemen; they think that our sexual habits should follow "caveman sexuality" as well. As fun as caveman sex sounds, Zuk again uses an educated evolutionary argument to show that there has never been one single manifestation of human sexuality. Following the logic that people have evolved to eat different things at different times (yes, in the time since the paleolithic), Zuk argues that humans have evolved to enjoy a spectrum of sexuality, ranging from stoic monogamy to swinging polygamy. Generally, the form of sexuality present in a particular culture is dependent on the environmental factors that influence how reproductive success is maximized.

The paleo-lifestyle argues that cavemen were polygamous and that our modern divorce rate and marital conflict comes from our instance that monogamy is the only option. Paleo-lifers argue that in mammoth-hunting and loin-cloth-wearing times, many people would act as parents to many offspring whether they were the actual biological parents or not. Babies, they argue, are raised by a community, not by a pair, and our insistence on monogamy also disrupts healthy infant development. This makes sense: we could have only evolved one way, and must still be that way, right?

If you've been following this blog, you'd know that that argument reeks of partially digested mammoth, and Zuk carefully demonstrates why. She describes anthropological studies on human sexuality in various cultures and shows that different human societies, living at the same time--but in different places--have different ways of doing things, so to speak. For example, children of the polygamous Gusii people of Kenya are "better adjusted, more empathetic, and more independent if they had strong attachments to at least one other person besides a parents while they were growing up". Tertiary helpers  might help children learn skills their parents may not know very well, and can help watch children if the parents need to do some other task. 

However, in the partially polygamous Dogon society of Mali, polygamy is associated with decreased survival and health of the children of second wives. In this context, the children of a man's first wife are prioritized over the children of second wives, likely due to increased resource competition. In this society, children of monogamous parents are better off than many of the children of polygamous parents. 

So it seems that in some environments polygamy is best, while in others monogamy confers the highest fitness. (I do acknowledge that both cultures I described have some degree of polygamy). The point is that there is no single "best" form of human sexuality. Thousands of years of evolution and adaption to different environments has given rise to the complex and seemingly contradictory face of human sexuality. Is the high divorce rate really a problem? Or are we living in a world of serial monogamy? What does our modern conception of sex have to do with horny cavemen? Well, one thing, to be sure: be it during the paleolithic or the anthropocene, when the gears of human sexuality get crankin', who doesn't want to don a loin cloth, run through the wild, and let loose the most primal of all yells? 

Week 5: Life Ascending Final Thoughts

Life Ascending surprised me truth be told. As I mentioned in my first post I was concerned that Lane would focus too much upon anthropomorphic view and was pleasantly surprised to see that this was not the case. Lane does focus heavily upon a human centered viewpoint, which is to be expected but I was pleased to see that he based many of his arguments in other contexts other than the human one. One example of this is the death chapter where Lane describes how death could have arisen from a war between bacteria and viruses developing an arms race of toxin and anti-toxin. Death is traced from its basic roots through the incorporation of mitochondria into host cells and the advent of multicellular life explaining how death could be brought into the host cell via a fully formed apparatus in mitochondria, and how death would be preserved as a mechanism to keep differentiated cells working as a cohesive unit. This allows Lane to bring the evolution of death and aging into the human context discussing antagonistic pleiotropy and free radical affects. Lane uses these smooth transitions from different aspects of evolution to the human perspective to great affect. These transitions capture the average readers attention while simultaneously educating them about aspects of evolutionary biology they would never think of on their own.

Also the more I read the more I became convinced that Lane's praise of natural selection was not as overbearing as I had feared at first. Natural selection is still described in a glowing light but Lane points out repeatedly that natural selection can only within the historical context of evolution and is not goal oriented. While this might seem like beating a dead horse to students in an evolution class, but when viewed from the perspective of a member of the general populace trying to learn more about evolution it helps show how natural selection actually works. I also have changed my mind about Lane's chosen topics as I appreciated how they were presented. The topics were kept broad an attention was applied to how they evolved outside of humanity.

The final thought I have from the death chapter is over Lane's argument about antagonistic pleiotropy, mainly how can we expect it to evolve in the future. If people start having children later and later as is the trend in modernized countries what evolutionary changes can we expect?

Week 5: Life Ascending: Final Thoughts

Life Ascending brings on a new perspective regarding evolution.  Rather than simply explaining what evolution is and how its mechanisms work, Lane uses ten major adaptations.  Each major adaptation discussed in the book has a unique perspective that specifically demonstrates the mechanisms of evolution.  I really enjoyed reading Life Ascending for this very reason.   Through each major adaptation discussed, I was able to discover more about how and why specific mechanisms of evolution led to the creation of that adaptation.  Also, each chapter examined various theories and ideas biologist share today.  For example while talking about the evolution of DNA, the theory of primordial soup was observed, and while discussing sex, the red queen hypothesis was reviewed.  Not only are major adaptations and mechanisms of evolution discussed, but also the theories and ideas behind them are included.  This provides a broad range that will help any reader better understand evolution.  Overall, I believe this book is both thought provoking and beneficial for any person who wants to learn more about evolutionary biology.

Natural Security: An Explanation of Our Biggest Threat

An Evolutionary Look at Religion

The book, Natural Security, described religion's function in society as "moral legitimacy to their cause (Juergensmyer, 2004)." I found this to be true with the history of my own religion, Catholicism. During the crusades, the Catholics tortured, martyred, and stole from the Muslims in a holy war. I think it is interesting the way Raphael Sargarin describes religion in an evolutionary context. He says, and I agree, that religion served the function to "inspire group commitment and individual action." So my question was sparked by how high rates of atheism are hurting evolutionary theories of religion which Sagarin mentioned on page 109. My question, If religion is advantageous to creating group unity, and we are a highly evolved species, why is atheism growing at such a fast rate?

My evolutionary explanation for this question is that religion may be a vestigial social organ. There is the possibility that in the past, group cooperation was more necessary with the help of others. In modern countries, individuals can now attain everything they need on their own because of advancements in technology.  Now that the trait, group cooperation, is no longer being disproportionate selected for, the possibility for the social organ to change from drift in areas where religion isn't an attractive force is great. It is important to include that this description of religion is not mutually exclusive with someone who believe in a specific religion. I feel that society in general tries to believe that science and religion are forces that are in a constant struggle for existence.

This connects to the overall themes in the book by explaining why most of our current conflict stems from, terrorists. Differences in thought processes have evolved separately and, in order to persist, "demoniz[ed] those with opposing views" (page 107). So now it is the very cohesive units that evolved to bring us together, religions, that are creating the current conflict and biggest threat we face as a species.

Paleofantasy: Week 5

I really enjoyed reading Paleofantasy and especially liked Zuk’s easy to read yet informative writing style. Zuk did an exceptional job presenting information to support her view that there is not really a specific way to emulate a perfect paleo lifestyle that humans are supposedly better suited to because this never really existed in the first place, hence the name “Paleofantasy”. She provided numerous great examples throughout the book to support her claims and I really learned a lot about human evolution from reading this. I especially liked “The Perfect Paleofantasy Diet” chapter where she stated that “the notion that humans got to a point in evolutionary history when their bodies were somehow in sync with the environment, and that sometime later we went astray from those roots…reflects a misunderstanding of evolution. What we are able to eat and thrive on depends on our more than 30 million years of history as primates, not on a single arbitrarily more recent moment in time” (120). I felt like this quote summarized not only how she viewed the idea of a paleofantasy diet but also the basis of what she described as other paleofantasies, whether it be in the realm of exercise, family, or how to deal with sickness and health. Overall, I am glad that I chose to read this book. I was not expecting Zuk to take the stand she did but really liked how she presented her information and the interesting examples she gave to support her claim that humans are still evolving and are not the same as they were in the past.

Paleofantasy Post #5

At the conclusion of Paleofantasy, I can say that, like many others, I really enjoyed reading my book of choice. Marlene Zuk does a good job of addressing many ideas that humans have misconstrued to due misinformation or belief, and she does so using the four mechanisms under which evolution may occur in great detail. Zuk's information definitely enlightened me to new views on various topics and provided me with a new way to look at certain aspects of our culture.

My main interest in this book stemmed from the popular Paleo Diet that I mentioned in my first post. Did Zuk address this fad in her writing? I would say yes, but in a different way than I was expecting. Instead of blatantly saying that eating the way our ancestors did is completely wrong, she instead suggested that such strict dietary adherence may not fit well with our bodies today. In essence, she debunked it in a milder form than I thought she would. In her final chapter, she sums up this idea nicely by saying that "sedentary living is clearly linked to poor health, but we do not have to emulate a mammoth-spearing caveman to remedy the problem" (Zuk 270). Basically, we do not need to adhere to extremes for every problem we encounter.

I can honestly say that I have no particularly negative critique about this book. Like I said above, Zuk prevents all information in a very clean manner and has countless sources to back up her claims, but there were certain topics that tended to drag past their informative value which caused me to lose interest at times. I loved how the topics she discussed could be related to everyone in some form or another. Overall, the simplicity in which Zuk presented the information lends the book to all audiences. Paleofantasy allows us readers to appreciate our connection to other species, which I believe is an important link that humans need to come to terms which to facilitate correct thinking of evolution.

Week 5: Needy Noses and Closing Remarks

We humans can pick out 10,000 different odors with our noses. This amazing level of specificity is only possible by the highly specialized proteins in our noses that attach to a unique odor and tell our brain what we're smelling. Shubin not only discusses the extraordinary function of noses, but also talks of the nose's function as an indicator of relatedness. He says,

"inside our noses is a veritable tree of life."

This is analogous to the saying "a picture is worth a thousand words." In humans specifically, we can determine the amount of scents we have and the amount we've lost due to mutations. Shubin points out that interestingly enough, organisms more closely related to humans have lost the exact same scent receptors from the same mutations that removed them from humans. I found it really interesting that mutations removing scent receptors that occurred further down the line of descent of mammals were conserved in humans and could be used as a biological clock to track moments of divergence.

As I finish Your Inner Fish, I'm left with a sense of fascination by the magnitude of examples that Shubin was able to provide throughout his text that supports evolution and the fact that all life descends from a common ancestor. Whether it was about similar body plans or the structure of our hands, Shubin continually connected everything back to this main argument. I found reading his book a breeze because of the constant connections he'd always make to common descent. Each chapter had a formulaic format to it: Shubin would present a discovery, give background information about the discovery, go back to discovery, then connect it to the larger picture. By being able to follow this formula, I was able to more easily comprehend the different enigmas he'd give and not be muddled down in new terminology or concepts.  

Week 5: Last thoughts

Upon my completion of Your Inner Fish, I can honestly say I enjoyed the book and would recommend it to many others to read. The manner that Dr. Shubin wrote, made it so I could easily relate the ideas written to what I have previously learned. I was able to understand his thought process and the connections Shubin made and found them fascinating and intriguing. The one thing I was not a fan of was the negativity that came into play near the end of his book. I guess in a way Dr. Shubin was not being negative but only telling the truth of the human body. He spoke of the issues and negative aspects that have developed through the evolution of humans. The list he gave was nowhere near complete, which in my mind is unsettling. Such is completely understandable and logical, however I would have wished the conclusion had focused more on summarizing the amazing and positive aspects of the human body that have come to be from the original fossil, Tiktaalik, that he found. I suppose my opinions are conflicted. I wrote that I wish it was more positive and focused on our accomplishments, yet that was evident in previous areas of his book. I also understand that the human body has many aspects that seem to be ridiculous in their formation and function, which was also evident in his book. Overall, I understand why Dr. Shubin concluded the book in this manner despite my wanting it to have been slightly different, but life is not perfect and neither is our body.

Week 5: Turning Back the Hands on our Biological Clocks

A simple way to consider the costs/ and benefits of death is in the study of the Brook trout.

Over time, the lifespan of the trout was quadrupled from 6 years to 24 years after the stressful ‘cost’ of sexual maturation was delayed. In class we discussed these cost/ benefit trade-offs and we learned that in many cases, longevity and number of offspring are inverses of one another. Death or senescence, in many ways, is as a by-product selection for alleles that enhance growth and reproduction early in life. There is an inherent trade-off between investing in reproduction and investing in body maintenance. Old age, (as stated by Medawar in Life Ascending) is the decline of genes that go on operating well after they should be. For humans, the elimination of infectious diseases as well as the removal of predation risks allowed us to double our lifespan. Modern-day approaches to death correspond closely to Medawar’s concept of late-acting genes.

Have we done this without any obvious penalties?

Longer lifespans are known to be associated with accumulation of free radicals and decreased telomere length. Are free radicals and shortened telomeres symptoms of old age or the causes of old age?

In Life Ascending, Nick Lane argues that “death is not only inevitable: it is controlled by the fates programmed into the very fabric of life” (261).

So, is there no way we can avoid aging?

I would argue there are ways in which we can change the route of our programmed paths. One example of this is one we have touched on in class which is caloric restriction. By reducing the amount of food consumed, the body undergoes less stress (as well as produces less free radicals) to convert food to energy. In some ways, caloric restriction allows us to trick the body back into youth. There are also genes that cause predispositions to certain diseases depending on how risky we are (i.e lifestyle, eating habits ect.). However,  the genomic level blind to certain diseases. For example, selection cannot purge harmful mutations that have deleterious effects later in life such as Alzheimer’s disease and Hamilton’s disease. Also, if it takes two copies of the gene to cause deleterious effects to the individual, the gene will not be purged. Current findings suggest that genetically-caused diseases are linked to biological old age rather than chronological time, meaning our biological age is not time-dependent, but rather damage-dependent. Therefore, there is some hope for us to alter the effects of some but not all disease-related genes.

More to Consider:

1. Is aging inherently untreatable? Are we only able to enact change on the symptoms of aging?

2. What unit(s) of selection caused the invention of “death”? On the level of the individual? On the level of the gene?

3. Also, for those of you who are reading Life Ascending, did you feel like he was purposefully leaving things out of the discussion on death? I noticed this chapter was lacking information on diminishing telomere length in cell replication, which is a key component of cell deterioration and ageing. I am not sure if this was implicit or not?

Week 4: TEETH!

In the 4th chapter of "Your Inner Fish," Shubin specifically talks about the evolutionary importance of teeth and how it evolves from the simple teeth of a lamprey to the highly-specialized teeth indicative of the mammalian condition. Being very interested in dentistry and wanting to expand upon what Shubin said,  or this week  I'm going to focus on the implications of mammalian teeth specializations by showing one of the figures from my vertebrate evolution textbook that depicts the teeth variations from ancestral mammals (on the left) and more derived mammals (right). As you can see, the more derived mammal has a "caninelike tooth" along with smaller teeth towards the front. This marks one of the first changes to modern-day mammal dental formulas. More importantly though, teeth specializations represent major changes in how organisms went about eating food. Canines promoted grasping of food, incisors were used for tearing/shearing, and molars specialized in grinding. Prior to teeth specializations, virtually all organisms implemented a simple method of tearing off food and swallowing it, NEVER chewing. With the advent of molars, mammals became the first organisms to be able to chew their food, allowing many previously-unoccupied niches to spring up (large rise in herbivores). In my opinion, mammals owe much of their ecologic success to these dental modifications. It allowed them to easily outcompete birds, snakes, lizards, and other terrestrial vertebrates by being able to adapt a whole variety of eating methods that minimized bodily harm, vulnerability to other predators, and maximize advantages over food/prey. I could keep going on with this for pages on end, but I just wanted to share a side story about Shubin's talk of the evolution of teeth because it's really amazing how important teeth are to the success of mammals.

Nature finds a way

While the seemingly perfect and beautiful complexity that results from evolution is amazing, I find that one of the most fascinating things about evolution is how natural selection favors what works best, not what is perfect. Zuk demonstrates this by describing a curious change in cricket morphology and behavior as a result of rapid evolution.

She studies the relationship between parasitoid flies and their cricket hosts. When the flies locate calling male crickets by the frequency of their calls, they lay eggs inside the crickets' bodies, which then hatch and devour the cricket from the inside out. Nature finds a way, but sometimes its a pretty gruesome way... This puts male crickets in a conundrum: males must call to attract females, which is necessary for reproduction; but calling also attracts parasitoid flies, which is detrimental to survival. What's a guy to do?

What she found is incredible. In a short number of years, many (but not all) male crickets lost the morphological feature which allowed them to call, thus preventing parasitism. This finding not only demonstrates that evolution can occur rapidly, but also presents a new interesting question: How do male crickets that don't call continue to reproduce if females can no longer find them (which they do by following the sounds of the male cricket's mating call)? Zuk's answer is one of my favorite explanations in the book because it demonstrates the maxim that nature finds a way:

"The answer is turning out to be complicated, with the females apparently willing to mate with the silent males as long as the males are near one of the few remaining callers"

Woah. So these silent males have minimized the costs of calling (parasitism) while mooching the benefits of calling from their noisy neighbors. They might not enjoy as much fitness as they would if there were no parasitoid flies at all, but some fitness is better than no fitness, and evolution isn't perfect. It just finds a way.

Also, the finding that silent males mooch off of the calling males raises a series of new questions: Why didn't this strategy evolve in the first place? Even in the absence of parasites, calling probably puts males at a higher risk of predation from other predators, so it seems that, for at least a portion of the population, silently waiting near a calling male might yield more fitness than actually calling. The appropriate strategy might then be maintained by frequency-dependence, such that being a caller or a mooch is dependent on how common the one is to the other in the population.

The fact that this behavior didn't evolve in the past suggests that there is more benefit to calling than allowing a female to find you. It may be that females are choosing males bast on the quality of their calls, not just on their ability to find them. If this is the case, how are females assessing the quality of silent males? Are they just getting fooled?

I love how an answer to a question leads to even more questions. Nature may always find a way, but biologists can't always explain it. But we try, and often do.

Favorite Passage

"We would never have scales, feathers, or breasts if we didn't have teeth in the first place." 

This phrase really caught my attention when I was reading Your Inner Fish. Prior to reading the book, I had no idea how much teeth had to do with paleontology and the connections that are made with our ancestors. Not only did he describe the connections teeth have between different species and how they are related but also how important teeth development along side the development of other tissues and traits is. I really like how this quotation allows the connection between different species and traits such as having breasts or feather still can be related by the commonality of teeth development. I had always heard on television criminal shows how helpful teeth were in identify people and allowed investigators to understand a lot about bodies they found, but never did I fully understand what this meant until reading Your Inner Fish. The way Shubin writes is very clear and helps me understand and relate things in my life that I never knew had connections before.