Something else

Objective I: Articulate the relevance of biological “laws”, findings, and methodologies to navigating nature in the future

Just like nature, the definite laws of biology are subject to ebb and flow. The laws proposed by Dunn are malleable guidelines meant to outline the course of nature in the future. That said, there are two overarching groups of laws. They are bias, and evolution by natural selection. The latter is comprised of terrain-organism relationships, and species interactions. The downstream effects of minding these laws are as Dunn says: they will guide us to sustainability, and free us from an impending future of water, pests, parasites, and hunger (Dunn 12,13). Therefore, as nature in the future is navigated, it is essential to mind these laws, and the outcomes of studies which bolster them.

Bias bleeds into just about every facet of biological study, thus it must be included as its own division. One facet of the law of bias revolves around anthropocentrism (Dunn 11). The mindset is characterized through how “every animal species has a perception of the world framed by its own species” (Dunn 11). The second facet of the law of bias is Erwin’s law (Dun 30). This, of course, is fueled by an anthropocentric through process that subconsciously lives within us—if we cannot see it or it does not directly affect humans, it does not matter or exist. An example of the law of bias comes from a diagram by Bar-On et al. (2018) that depicts the biomass distribution on earth. As intended by Professor Brown, when she displayed this chart, the results shocked myself and my peers. Humans are such a tiny portion of earth’s biomass, but we view ourselves as the top of the food chain/dominant species. There is also just such an ungraspably large number of plants, bacteria and more exist; so many life forms are understudied because humans do not see them, or they don’t directly benefit or harm us. The first people to attempt to compile all living things into a list failed to include bacteria or fungi (Bar-On et al., 2018). Those just so happen to be two of the largest categories on the aforementioned list. As one can see, bias has blinded proper understanding of organisms and research on them. In the grand scheme of things, the “limits of our perceptions” (Dunn 12) have hindered us despite all of the anthropocentric progress we have made. Thus, our outlook on the natural world is skewed, so how could one even try to predict it? There is also unlikely to be a global change in this mindset (Dunn 12). So, selfish human beings will continue to wreak havoc on organisms that we do not see, think, or care about, and Dunn’s warnings of destruction will come true unless we heed to the warnings from the law of bias.

The next law of biology is evolution by natural selection. Within this law are two subdivisions of laws: the law of organism-terrain, and the law of species interactions, which contain their own subdivisions of laws. In natural selection, only the favored organisms live to pass their genetic information down, and thus a more ideal species evolves (Dunn 6). Therefore, this overarching law guides biologists in their understanding of how species will develop, and which species will survive the cumulative elements of climate change and thus is necessary for outlining nature in the future.

The sub-law of organism-terrain relationships is a division of laws that puts up guardrails for scientists who try to envision who the species of the future will be, and where. No matter the organism, it will always have some environment for which it lives. That said, this category is comprised of the laws of niche, corridors, diversity-stability, and species-area. An example of both corridor and niche is how since icebergs are projected to melt, a corridor will be created for salmon to swim through (Pitman et al., 2021). Many of the new areas will suit them, and their niche will expand (Pitman et al., 2021). Therefore, in order to navigate the natural future, biologists must be able to predict where species might be able to bleed into as the climate shifts and opens new corridors. If not, then they will be unable to predict the effects of these niche shifts for the original organism, native organisms, and the environment itself. By following this law, scientists are able to apply modeling methods like the latter to other future groups, who also have habitats that are projected to change.

The species-area law is also grouped into this sub-category. In order to survive in an area, a species must be sustained by its environment, or else it will die (Brown, 2022). This law is needed in the face of a changing climate. As the world warms, many organisms will struggle when they find their niches gone. Many will then congregate in the same area. In order to maintain the greatest number of organisms in a location, the number of organisms that the environment can hold will be very important in which understanding which species will need to compete for niche space. This law will guide those future situations.

The diversity-stability law is commonly applied to agriculture type species interactions, where more growing success is fostered by more species in the cultivated area (Dunn 11). Biologists used the species-stability law to back a study that allowed for more crops to survive by actively increasing the number of species in rice plots in China (Zhu et al., 2000). When the non-disease resistant rice crop was joined with disease resistant rice, more rice survived disease, and more rice was yielded overall (Zhu et al., 2000). Therefore, by inducing plot heterogeneity for the rice crop locations, the original rice was better suited to overcome the blast that had harmed it in preceding years. Thus, introducing the weaker rice to the resistant rice allowed it to work with its new diverse environment to survive the blasts. Biologists who heed to this law will be able to navigate the questions of which ecosystems will thrive, why, and how to save others.

The second sub-set of laws is referred to as species interactions, and it creates a guide for biologists to refer to when wondering how organisms will evolve and outcompete each other in the rapidly changing future. Within this group there are the laws of escape, dependence, and diversity. The clearest example of a law that belongs in this division is that of dependence. Species which depend on certain microbes evolve unique methods of carrying the microbes further. Take the leaf cutter ant—it carries a mutualistic fungus in a small pouch under its mouth (Dunn 187). The ant has evolved to produce a stable home on its body for this fungus, and in return the fungus provides aid for the ant it would not otherwise receive. Thus, the species interaction allows both species to persevere into the future.

The next law that fits into this larger category of species interactions is the law of escape. Humans are not exempt from any of these laws, including this one. When some people moved out of tropical climates, our species escaped the parasite Malaria, which lives on a particular mosquito called Plasmodium falciparum (Dunn 79). Since leaving the malaria zones, there have been longer life expectancies and less infant mortality (Dunn 79). Thus, humans have benefitted from our ‘escape’, which confirms the law. In terms of predicting the future, this law provides a predictive measure for which organisms will succeed, and which will not—the ones that can flee their antagonists will likely make it into the future.

Finally, there is the law of cognitive buffering which outlines the difference between organisms that use inventive intelligence versus autonomic know-how (see Objective II). To be able to craft malleable responses using thought processes is an integral characteristic that promotes survival. Thus, in order to navigate the changing future organisms must be able to think critically to survive against one another. In a competing pair of species, only one can win. 

That said, there are only two laws of nature: bias, and evolution by natural selection. To understand that humans are not any more important than other species will shift research directions, and lead to people caring more about species they might not have considered before. By doing this, greater respect for our natural world will increase. Thus, we might just be able to appreciate nature enough to save it, and us. Evolution by natural selection is absolutely integral to navigate nature in the future. Being able to predict which species might outcompete each other, or which organisms will evolve to some changing environment, is necessary for envisioning what the coming years will be comprised of, and why.

Annotated Bibliography

Bar-On, Y. M., Phillips, R., & Milo, R. (2018). The biomass distribution on Earth. Proceedings of the National Academy of Sciences, 115(25), 6506–6511. https://doi.org/10.1073/pnas.1711842115

The methods behind Figure 1 are that the researchers compiled data from hundreds of other studies which looked at the biomass of earth’s organisms.

On figure, animals are only 2 Gt C, and humans are only .06 Gt C.

Brown, M. (2022, February 2) Day 3 (Nature in the Future). HWS Canvas Biology Seminar.

https://canvas.hws.edu/courses/3412735/files/folder/lecture%20slides?preview=228527681

The smaller the area of the environment is, the less species it can physically support.

Dunn, R. (2022). Natural history of the future. Hachette UK Distribution.

Dunn says that the law of anthropocentrism is that “as humans, we tend to imagine the biological world to be filled with species like us, species with eyes, brains and backbones” (11).

Erwin’s law, that life tends to be much less studied than we think it is.

According to Charles Darwin, in each generation of organisms, nature ‘selects’ upon some individuals due to their traits and behaviors.

A niche is an area an organism can live where it is adapted to the biotic and abiotic elements of the environment. In relation, a corridor is a connecting environment from niche to niche for an organism to cross as the climate changes.

The species-area law predicts that there is cap for how many species can live on a particular area. This is generally limited by because there are more resources and thus less competition for survival.

The diversity- stability law says that the more diverse an ecosystem is, the more stable it will be.

Dunn says the law of dependence states that all species will rely on other species.

Dunn says that the law of escape describes how species will do very well when they have escaped predators, parasites, and other harmful organisms.

Objective II: There are two types of intelligence—inventive and know-how. Inventive intelligence is when the organism can modify and invent behaviors to solve new problems in new conditions. From there, they learn to repeat the solutions that they reasoned through. Know-how intelligence is when the organism can only do a very niche set of tasks, but they can do them very well.

Organisms with inventive intelligence have big brains relative to body size, whereas know-how organisms have small brains relative to their body size.

Birds with inventive intelligence are predicted to thrive in a variable future. Know-how birds are predicted to suffer

Pitman, K. J., Moore, J. W., Huss, M., Sloat, M. R., Whited, D. C., Beechie, T. J., Brenner, R., Hood, E. W., Milner, A. M., Pess, G. R., Reeves, G. H., & Schindler, D. E. (2021).

 Glacier retreat creating new Pacific Salmon Habitat in western North America. Nature Communications, 12(1). https://doi.org/10.1038/s41467-021-26897-2

Climate change is causing massive changes in earth’s environments.

The researchers created a model of the change in the masses of 315 glaciers. They also modeled the habitat potential for the salmon streams.

By 2100, there will be 6,146 (+-1,619) km of new potential steam habitats for Pacific salmon. Of those approximately 6,146 new stream areas, 1,930 (+-569) km are viable for hosting the reproductive habits of salmon and their offspring.

Zhu, Y., Chen, H., Fan, J., Wang, Y., Li, Y., Chen, J., Fan, J. X., Yang, S., Hu, L., Leung, H., Mew, T. W., Teng, P. S., Wang, Z., & Mundt, C. C. (2000). Genetic diversity and disease control in Rice. Nature, 406(6797), 718–722. https://doi.org/10.1038/35021046

Biologists placed rice crops that were genetically resistant to disease in a monoculture of susceptible rice crops.

From 1988 to 1999 the researchers utilized 15 rice fields in China

When introduced to disease resistant rice crops, the susceptible crops had an 89% greater yield and the blast was 94% less severe than usual.

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Objective II: Integrate the four complementary approaches of understanding biological traits and behaviors (structure & function, development, adaptive significance, and phylogenetic history) to predict biology in the future.

There are four complementary approaches of understanding biological traits and behaviors (structure & function, development, adaptive significance, and phylogenetic history) that work to predict biology in the future. Structure and function as a way to predict the future is demonstrated by the law of cognitive buffering of the crow. Development as a way to predict the future is exemplified through the learned behaviors of resurrected species. Adaptive significance is shown as a predictive lens using the example of chlorophyll retention on coral. Phylogenetic history is proven to be able to predict biology in the future using the example of turkeys on college campuses. If any of these four approaches of understanding biology is ignored, then the biological future cannot be fully explored. 

The natural world is changing rapidly, and not all organisms will be able to endure it based off of their structural traits. A structural trait of the crow is that they are known to have big brain relative to their small body. This feature is key to them being able to use their intelligence in creative ways, which promotes their survival (Dunn 125). A bird like the crow which uses inventive intelligence can cope with the changing future as the world rapidly changes (Dunn 128). Therefore, they are more likely to survive (Dunn 128). The change is largely characterized by urbanization and expansion. The structure of the crow’s proportions lends to them being able to adapt quickly to new scenarios arising all of the time due to urbanization. If the bird did not have a big brain relative to its body, it would be limited to autonomic know-how which does not bode well for their survival into the future (Dunn 129). Thus, their species would likely not be found in the future. If this pattern holds true, then it is possible to predict what species will survive this period of time in the natural world. Structure and function cannot be left out when understanding biology because of these very important patterns that dictate species survival. In the scenario where structure and function are ignored, biologists would be less likely to deduce which species of bird is most likely to survive urbanization. If that is the case, then how are biologists to know what species will be around in five, ten, fifteen years that can have the potential to shape ecosystems, and more? There are many cascading effects that can arise from the extinction of just one species. Many species are integral to major biological systems. For this reason, using structure and function to being able to predict which will stay and which will die off is key to envisioning nature in the future.

If biologists cannot understand how different necessary traits in organisms develop then there is a shroud over the foresight of resurrected species. The development of resurrected species is a popular topic of debate for scientists due to its effects on the future. Many of those people included in the discussion exercise concerns about the ethology of resurrection. They wonder, if the resurrected species does not have its biological parents as its parents, will the resurrected offspring still learn the behavior? The underlying question here is how behavioral traits get taught to a species. Let us say a biologist was planning on resurrecting a leaf-eating dinosaur. Is this trait learned, or innate? Across its lifespan, when does the trait of finding good leaves come to fruition? Is it developed in the womb, or is it when the creature can walk, it copies its mother as she finds leaves to eat? If scientists do not consider the development of the organism, there is a chance that the resurrected organism would die off again because it does not know how to find the right leaf with the proper nutrients. Or perhaps it would learn the wrong behavior and cause unforeseen havoc. Therefore, the resurrection would be for naught and the species the resurrected organism was perhaps created to support will fail.

Knowing how and why a trait has evolved is also integral in predicting nature in the future. For instance, a trait of many coral species is that they have coloration. A large proportion of the coloration is due to microbial symbionts influencing the coral’s phenotype (van Oppen et al., 2015). Another function of the corals’ microbial symbionts is that they allow for an increased ability to tolerate stress, such as rising ocean temperatures (van Oppen et al., 2015). Thus, the coral keeps the symbionts around across generations because they aid them in survival. However, since the corals are bleaching and dying scientists are looking to enact different methods of assisted evolution to help them (van Oppen et al., 2015). One of the methods is through introducing to different combinations of the microbial symbiont belonging to the genus Symbiodinium (van Oppen et al., 2015). Since the biologists know what causes the trait for coral color and also what the microbes do, they can use that information to save the corals through assisted evolution. Without understanding this relationship, biologists would have one less way to save the corals, and they would likely all die in the face of the changing climate. Corals are integral in maintaining multiple other species. Thus, if they die, then there is a cascade of other organisms that will suffer and potentially become extinct as well. However, since the coral colorations’ adaptive significance is understood, scientists can predict that colors have a higher chance of surviving into the future than before. Without this understanding, this method of assisted evolution would be impossible.

Turkeys are able to live in both rural and city environments. Under the biological lens of phylogenetic history, one could ask: what about turkeys lets them also live in a city? Why and how did this trait evolve? Like most organisms, turkeys tend to prefer areas with bountiful food, and limited predators. On city-based college campuses such as Harvard in Cambridge, MA, both of those things exist in abundance (Smith 2021). Furthermore, after the previously endangered species made a comeback in its purposefully expanded habitat, there was leakage into cities as well (Smith 2021). Therefore, the turkeys have evolved to have a very large potential range of places to live. This lens is incredibly helpful for predicting nature in the future. Since scientists can figure out the niches of organisms, they can deduce which have ranges large enough, and near enough to a city that there might be a spillover into urban life. Scientists can also use the same conservation method that saved the turkeys and apply it to other dwindling species that could flourish in an urban environment. Either way, this biological approach leads to scientists being able to understand what species could inhabit the cities of the future. 

That said, all of the four biological approaches are integral in predicting nature in the future. Without form and function, biologists would have less of an idea which organisms will be able to survive a variable future. Without development, resurrection could bring back a doomed species, and thus fail the organisms it was meant to support ending in many extinctions. Ignoring adaptive significance can result in the inability to follow through with assisted evolution, thus endangered species will likely die. Last but not least, no regard to phylogenetic history can end in the inability to predict where species can expand their niche to. All four of these approaches combined create a full picture of biology in the future.

Annotated Bibliography

Dunn, R. (2022). Natural history of the future. Hachette UK Distribution.

There are two types of intelligence—inventive and know-how. Inventive intelligence is when the organism can modify and invent behaviors to solve new problems in new conditions. From there, they learn to repeat the solutions that they reasoned through. Know-how intelligence is when the organism can only do a very niche set of tasks, but they can do them very well.

Organisms with inventive intelligence have big brains relative to body size, whereas know-how organisms have small brains relative to their body size.

Birds with inventive intelligence are predicted to thrive in a variable future. Know-how birds are predicted to suffer

Sayol F, Sol D and Pigot AL (2020) Brain Size and Life History Interact to Predict Urban Tolerance in Birds. Front. Ecol. Evol. 8:58. doi: 10.3389/fevo.2020.00058

A large brain size in respect to body size generally increases urban tolerance.

Rothschild video

A common concern about the ethics of resurrection is what will happen if the resurrected offspring don’t have their biologically matched parent in terms of the chance to learn necessary behaviors.

van Oppen, M. J., Oliver, J. K., Putnam, H. M., & Gates, R. D. (2015). Building Coral Reef Resilience Through Assisted Evolution. Proceedings of the National Academy of Sciences, 112(8), 2307–2313. https://doi.org/10.1073/pnas.1422301112

The scope of epigenetics includes the microbe community that lives on, in and/or near an organism because of how microbial symbionts can affect the phenotype of the host.

The dinoflagellate Symbiodinium microbes incite the calcification that forms reef structures. Using Symbiodinium microbes from different thermal environments on corals can increase the range of thermal tolerance for the coral.

Smith, M. (2021, November 25). ‘As Turkeys Take Over Campus, Some Colleges Are More Thankful Than Others’. The New York Times. https://www.nytimes.com/2021/11/25/us/turkey-college-campus.html.

Conservation efforts to increase the population size of turkeys has led to them moving nationwide into cities, alleys, backyards, and colleges.

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Objective III: Detail human’s fundamental role on Earth at the levels of ecosystems, species, and genes.

As the self-proclaimed dominant members of the Earth’s diverse species, humans have played a fundamental role in multiple biological tiers including the ecosystem, the species within the ecosystems and their genes. Many biologists have dedicated research to understanding the ways in which humans have altered the organisms around us. Such research is done by Katherine Byrne and Richard Nichols on mosquitoes, Elizabeth Carlen, and Jason Munshi-Souths’ research about pigeons, and Campbell-Staton and colleagues’ study on elephants. That said, I will demonstrate how humans made a sizable impact on the natural world from genetics to ecosystems.

Humans have constructed large underground tunnels that present mosquitos with an entirely new type of playground that nature could never provide them with. The development of the new, unfamiliar, human-made ecosystem presented the species with a different set of obstacles to develop around, and because of this, the mosquitos needed to adapt in unprecedented ways. Mosquitoes adapt to the novel underground environment with its dark corners, puddles, and prey resources. Without human activity, the mosquitos likely would not have traveled to such subterranean areas. Thus, the actions of humans have caused a major shift in the lives of mosquitos.

It has become evident that the man-made underground tunnels have had a large effect on a species level for mosquitos. During this rapid urban development, mosquitos isolated into two species—aboveground mosquitoes and underground mosquitoes (Byrne and Nichols 1999). For instance, the preferred hosts of the aboveground mosquitoes are birds, whereas the underground type prefers humans (Byrne and Nichols 1999). Mating styles between the two types also differ. While the above ground mosquitoes mate in a cluster, the underground type has a one-one-one interaction (Byrne and Nichols 1999). There is even a difference in the ovapositioning of the two types—the aboveground type needs to feed to lay their eggs, but the underground type just needs a place where there is residual water (Byrne and Nichols 1999). The last example of how the two types differ is in their life cycles. The life cycle of the aboveground mosquito includes an obligate period of hibernation and diapause, while the underground mosquito is homodynamic (Byrne and Nichols 1999). However, an alternative hypothesis for the origin of the subterranean mosquitos is they are just nonnative species and moved from native range to nonnative range and moved to subway (Byrne and Nichols 1999).

Genetically distinct genomes of mosquitos evolved due to the human construction of the London underground tunnel. Byrne and Nichols deduced that there was genetic differentiation between the aboveground populations of Culex pipiens and then the molestus underground species (Byrne and Nichols 1999). The genetic distinction also reaped the conclusion that there was no gene flow between the two species of mosquito (Byrne and Nichols 1999). In order to determine a speciation event, the researchers ran a breeding experiment. The results of the experiment yielded that there was no breeding compatibility with the above and underground mosquitos (Byrne and Nichols 1999). Without the tunnels, there two mosquitos would not have speciated in the way they have, i.e., the Culex pipiens trapped underground wouldn’t have genetically evolved into the new molestus species.

 At the ecosystem level, humans instigated rapid urban expansion which has led to a large area of mostly connected city space—the megacity. An example of this is the Northeastern megacity which spans from Boston, Massachusetts to Washington, D.C. (Carlen and Munshi-South 2020; Dunn 72). Pigeons experience rural areas as a barrier to gene flow, so with limited rural space due to the megacity, the pigeons can travel the entire distance of megacity in just one day (Carlen and Munshi-South 2020; Dunn 72). A city corridor is a pathway to environments which before rapid urban development would not have been possible.

Urbanization has caused a change within the Indian gerbil (Tatera indica) species. In the natural habitat of the Indian gerbil, they rarely encounter another, so they employ a scent based chemical flagging system (Schilthuizen 199). Conversely, in the city the gerbils are more densely collected—there is no need for chemical flagging to locate each other; the trait is being lost and the species is changing (Schilthuizen 199). Furthermore, if the city Indian gerbils were to be put in the wild with rural Indian gerbils, it is unlikely they would ever find a mate. This is a barrier to gene flow, and so there is a chance there would be a speciation event for the Indian gerbil. That said, humans have the potential to create a new branch of gerbil species with urbanization.

The genetic composition of pigeons has been impacted by the megacity. Carlen and Munshi-South (2021) calculated the genetic diversity among the pigeons in different parts of the megacity. The data from an estimated migration surface model and further charting largely suggests that gene flow is occurring through the corridors, or a continuous niche, between the cities because the pigeons in nine of the cities studied have overlapping genes (Carlen and Munshi-South 2021). However, there is a break in the megacity. A discriminant analysis of principal components (DAPC) for 35,200 genome-wide SNPs recovered from pigeons shows a break in the barrier between Boston and the rest of the megacities (Carlen and Munshi-South 2021). Thus, the Boston birds will exchange DNA more frequently than between the rest of the combined cities.

Anthropocentric activities involving elephant tusk harvesting have altered the Gorongosa National Park’s ecosystem. The tusks are tools that can dig out underground food, minerals, tear bark, and facilitate maintenance or change in the environments of other species (Campbell-Staton et al 1992). Due to how elephants are a keystone species, killing them off carries a large potential threat to biologically necessary megafauna (Campbell-Staton et al 1992). Outcomes of the tusklessness that have been documented are a shift in plant species, a decline in overall biodiversity, and more tree cover (Campbell-Staton et al. 1992). Ecosystems are in a constant and critical balance. When humans poached the elephants, that balance was put in disarray. A new, unnatural ecological scene took over what nature had curated.

Humans have altered how the Gorongosa elephant species look. Poachers during the civil war would only kill the elephants with tusks because they contained the ivory, thus a large number of their population was killed off (Campbell-Staton et al 1992). Tusklessness is a heritable trait. So when only tuskless elephants survived, they all mated with other tuskless elephants, and thus bred tuskless offspring which had the opportunity to survive due to how they did not have the desired ivory. The tusks of elephants are a common attribute to the species. Thus, humans have set Gorongosa elephants apart visually from the rest of the wilds’ species by becoming a selective force against them by eliminating the gene for tusks. 

Poaching drove the Gorongosa elephants to genetically alter into a tuskless species. The selection for tusklessness is guided by a selection on at least one X-linked locus, called AMELX, and then on one autosomal locus, called MEP1a (Campbell-Staton et al 1992). The significance of this research is that it reinforces the “proposed X-linked dominant, male-lethal inheritance” of not being tusked for the Gorongosa elephants (Campbell-Staton et al 1992). The short timeframe for the tusk-based selection, and the previous understanding of the tuskless phenotype before the bottleneck occurred both point to genetic variation at the aforementioned male-lethal loci as the cause for the growing population of tuskless males (Campbell-Staton et al 1992). Therefore, poaching brought forth the component of genetic change for the elephants as well.

Based on the examples of the mosquito, pigeon, gerbil, and elephant, it is evident that humans have played a fundamental role in multiple biological tiers. Such tiers include the ecosystem, the species within the ecosystems, and their genes. Whether it is for worse or for better, it is plain to see that humans have instigated countless impacts on the biological world around us.

Annotated Bibliography

Byrne, Katharine, and Richard A Nichols. “Culex Pipiens in London Underground Tunnels: Differentiation between Surface and Subterranean Populations.” Heredity, vol. 82, no. 1, 1999, pp. 7–15., https://doi.org/10.1038/sj.hdy.6884120.

How misquotes have been affected by urban structures.

Mosquitos isolated into two species—aboveground mosquitoes and underground mosquitoes

Byrne and Nichols deduced that there was genetic differentiation between the aboveground populations of Culex pipiens and then the molestus underground species

Campbell-Staton, Shane C., et al. “Ivory Poaching and the Rapid Evolution of Tusklessness in African Elephants.” Science, vol. 374, no. 6566, 2021, pp. 483–487., https://doi.org/10.1126/science.abe7389.

Elephants are the final example of a species altered biologically due to human pursuits, as seen in Campbell-Staton et al’s 2021 paper “Ivory poaching and the rapid evolution of tusklessness in African elephants”. During the Mozambican Civil War from 1977 to 1992, the elephants in the savanna Gorongosa National Park were poached for their ivory tusks.

Just one of these impacts would have a large domino effect on multiple other parts of the ecosystem.

The selection for tusklessness is guided by a selection on at least one X-linked locus, called AMELX, and then on one autosomal locus, called MEP1a (Campbell-Staton et al 1992). Research has shown that there is a link between AMELX and the male-lethal loci on the X chromosome in the elephants.

Carlen, Elizabeth, and Jason Munshi‐South. “Widespread Genetic Connectivity of Feral Pigeons across the Northeastern Megacity.” Evolutionary Applications, vol. 14, no. 1, 2020, pp. 150–162., https://doi.org/10.1111/eva.12972.

The article published in 2020 titled “Widespread genetic connectivity of feral pigeons across the Northeastern megacity” by Elizabeth Carlen and Jason Munshi-South provides an example for how humans have altered pigeon’s trajectories at multiple biological levels.

Urbanization has been proven to alter genetic patterns of wild populations. Therefore, the creation of the megacity can positively influence gene flow in how it creates one large viable habitat for the birds to mate in

While there was a significant amount of genetic variation between the Boston and Providence pigeons, they found clusters of birds with genetic similarity.

Dunn, R. (2022). Natural history of the future. Hachette UK Distribution.

Carlen and Munshi-South found evidence that the pigeons from Washington to New York City are interbreeding so freely that there is no difference between DC pigeons and Broadway pigeons.

Schilthuizen, M. (2019). Darwin comes to town: How the urban jungle drives evolution. Picador.

Urban gerbils are losing their scent-marking glands. 

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Objective IV: Demonstrate evolution as a unifying concept of organisms’ interaction with their environment via natural selection and human-assisted technologies (e.g., gene drives, assisted migration)

Evolution is a unifying concept for organisms’ interaction with their environment via natural selection and human-assisted technologies. Dunn, Schilthuizen, and many other researchers have found many different ways in which the unification occurs. Evolution unifies organisms’ environment via natural selection through the examples of the Peppered Moth (Biston betularia), and the European Robin (Erithacus rubecula) and the Bridge Spider (Larinoides sclopetarius). In tandem, human assisted evolutionary technologies have also propelled the unification of organisms in their environments as seen through the assisted heterogenous mixture of rice crops and assisted evolution of coral. Without these divisions of evolution, none of the organisms be discussed would be able to cope with their current environments, and the environments which wait for them in the future.

Biston betularia’s evolution through natural selection drove the adaptation of the dark morph to better suit its new and polluted environment. As industrialization in Manchester exploded, so did the levels of pollution, and the surrounding ecology and its organisms endured change in response through natural selection (Schilthuizen 82). The peppered moth, Biston betularia, has experienced a tumultuous evolutionary history, and its story is a crisp example of an organism adapting to its environment through evolution. It was properly adapted to the white lichen on the trees it prefers, but when the acid rain killed the lichen, and dark soot caked the tree, the moth was maladapted to the darker tree (Weiland 1999; Schilthuizen 86). This is when the dark morph of B. betularia become the properly adapted version of the moth in lieu of white morph because of birds which act as selective agents (Schilthuizen 88). Soon enough there are more black morphs than pale morphs because the pale morphs are subject to intense natural selection (Schilthuizen 84). The dark moths evaded the birds using their dark camouflage while the white moths were exposed and thus eaten at higher rates. Thus, the genotype for the light morph decreased. As more and more white morphs were predated out of the population, the black morphs increase rapidly as the population evolved to have a majority of dark B. betularia (Schilthuizen 88).

Another species to experience evolution through natural selection is the urban European robin, Erithacus rubecula. Rapid urbanization has a multitude of consequences, and one of them is noise. One example of a consequence is an immense increase in noise pollution (Schilthuizen 183). When considering E. rubecula as a domino in this downstream conundrum, an important fact about them to note is that they rely heavily on song to find mates (Fuller et al., 2007). If the birds are not heard, then they will not find a mate and not be able to produce offspring. Thus, they die without passing on their genetic information. The E. rubecula just could not compete with the intense noises of the city during the day (Fuller et al., 2007). However, the E. rubecula that sang at night when it was quieter were able to be heard by interested mates. Therefore, the birds which sang at night were able to reproduce and raise offspring. The shift from daytime singing to nighttime singing shows a selection pressure against daytime singing. Such a shift to a beneficial trait due to a selection pressure is indicative of an evolving species.

Artificial light’s effect on Larinoides sclopetarius, the Bridge Spider, is a third example of evolution natural selection that resulted in a better match to their environment.  It began when scientist Astrid Heiling noticed how the urban spiders she would see tended to build their webs near sources of artificial light on handrails (Schilthuizen 138). This was notable because L. sclopetarius are usually seen building their webs over water in both rural and urban settings (Schilthuizen 138). Furthermore, spiders tend to flee from and generally avoid bright light (Schilthuizen 138). However, the spiders that set up their webs near the artificial light caught four times more insects than the spiders that were in the dark (Schilthuizen 139). Results like that indicate that evolution has occurred for the spiders to shift their attractions to dark versus light so that they can better exploit their insect prey and promote their own survival (Schilthuizen 140). Thus, the fake light acted as the driving force for the L. sclopetarius’ evolution towards working with previously undesirable aspects of the city.

Through assisted evolution, the coral species can unify with their environment in a healthy and productive way. As of right now, coral reefs are under the pressure of climate change, and are struggling as a response (van Oppen et al., 2015). The evolution of the corals is too slow to match the speed at which the ocean is warming, and traditional tactics will not suffice anymore to save them (van Oppen et al., 2015). The goal of human interference tactics is that by interfering, the scientists can provide the coral with the tools through evolution that it needs to continue in the face of an unsuitable habitat. For instance, these methods would allow for the coral to make a recovery from small impacts and tolerate a stressful environment (van Oppen et al., 2015). By purposefully instilling these skills into the coral, the organism has what it needs to live in the environment successfully. Hopefully in the future it will continue to stand a chance to survive. Without human interference, the coral would not be suited to the changing climate and would die. Therefore, by assisting the coral with evolution, it has the tools it needs to re-unify with the environment that changed faster than it could evolve.  

Whether it was a bird evolving to sing at a different time to attract mates, or a coral acquiring rebound techniques, researchers have proven that evolution functions to benefit a species. Researchers such as Fuller and their colleagues (2007) and van Oppen (2015) found proof of this thesis when discovering that the effects of the evolution increased the organism’s fitness. That said, Through the examples of natural selection using B. betularia, E. rubecula and L. sclopetarius plus human assisted technologies as demonstrated through the coral, it is evident that evolution is a driving force between an organism and its environment.

Annotated Bibliography

Wieland, C. (1999). Goodbye, peppered moths: A classic evolutionary story comes unstuck. Creation, 21(3), 56.

Peppered moths are picked off by birds, and thus they gradually shifted from white to black wings to blend in.

The moth comes in light and dark (melanic) forms. Pollution from the Industrial Revolution darkened the tree trunks, mostly by killing the light-coloured covering lichen (plus soot).

Schilthuizen, M. (2019). Darwin comes to town: How the urban jungle drives evolution. Picador.

Between the years 1770 and 1850, the city of Manchester grew […] from 24,000 to 350,000 inhabitants.

During the city’s rapid expansion, there was an incredibly large increase in soot, sulfur, and nitrogenous gasses.

The black winged B. betularia is able to survive and produce offspring, which are also black. Soon enough, they are more common than the pale version.

The acid rain from the pollution killed the white tree lichen and then the soot stained the branches of the moth’s trees black.

Birds act as selective agents as said many times before by evolutionary theory.

When an experiment was run, 63 percent of the black moths were found to still be alive, but only 46 percent of the pale morphs survived.

In Europe, about 65 percent of people are exposed to background noise from their urban environment louder than constant rain. The animals in the urban environment have to compensate for this. 

Astrid Heiling noticed that Larinoides sclopetarius tend to build their webs near artificial light sources.

Spiders tend to flee from artificial light

Insects fly towards light, so spiders near light caught more bugs.

Heiling ran an experiment to test for a change in environment preference. The results were that all spiders chose the well-lit area. This indicates evolution has occurred.

Fuller, R. A., Warren, P. H., & Gaston, K. J. (2007). Daytime noise predicts nocturnal singing in urban Robins. Biology Letters, 3(4), 368–370. https://doi.org/10.1098/rsbl.2007.0134

Erithacus rubecula are reliant on vocal communication, and thus reduce acoustic interference by singing during the night in areas that are noisy during the day.

van Oppen, M. J., Oliver, J. K., Putnam, H. M., & Gates, R. D. (2015). Building Coral Reef Resilience Through Assisted Evolution. Proceedings of the National Academy of Sciences, 112(8), 2307–2313. https://doi.org/10.1073/pnas.1422301112

Coral reefs are dying due to global and local disturbances including warmer seas.

Some examples of human assisted technologies are stress exposure to incite preconditioning and transgenerational acclimatization though epigenetics, modifying the composition of the community of microbes associated with coral, and selective breeding to develop useful traits for survival.

Zhu, Y., Chen, H., Fan, J., Wang, Y., Li, Y., Chen, J., Fan, J. X., Yang, S., Hu, L., Leung, H., Mew, T. W., Teng, P. S., Wang, Z., & Mundt, C. C. (2000). Genetic diversity and disease control in Rice. Nature, 406(6797), 718–722. https://doi.org/10.1038/35021046

One way to aid crops in the plight against disease it to incite crop heterogeneity in monocultured areas.

Researchers planted diversified rice crops in a total of 15 townships in China. They looked to calculate the effects that heterogeneous the crops had on how severe the rice blast was.

The results were that when disease susceptible plants were placed in heterogenous plots with non-susceptible plants, there was an 89% increase in rice yield and the blast was 94% less deadly.

The results were so astounding that the rice farmers stopped using fungicide sprays.