Why the Zebra Got its Stripes: exploring the anti-parasite hypothesis

Review written by Laura W. Hirschfield, UG ‘24 (Neuroscience)

Scientists have continued to debate for centuries the reasons behind why the zebra got its stripes. The zebra’s pattern is rare in the animal kingdom, intensely expressed in both sexes, conspicuous, and yet, its utility is not apparent. Unlike the many other hoofed mammals, called ungulates, that also occupy the east African savannah, the stripes do not provide camouflage for any of the habitats zebras occupy.

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The Virus Microenvironment: How Cells React When Their Neighbors Get Sick

Review by Abigail Stanton (MOL, G4)

From the perspective of a cell, every viral infection is the start of a zombie apocalypse. One day you and your neighbor are working together in your quaint body community and then the next… they’ve changed. Your unrecognizable fellow cell becomes single-minded with its new obsession: making viruses. When it has spent all of its energy, it spreads the virus to all of its neighbors, turning them, too, into virus-building zombies. 

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Meant to protect, made to neglect: exposing parks’ true efficacy in keeping species safe

Review written by Natalie Wong (2025, EEB)

The term “protected area” in the context of wildlife preservation calls to mind an idyllic haven untouched by civilization, where all organisms have the resources they need to thrive. The expectation is that animals–particularly those facing endangerment or extinction–will be kept safe from the humans who contribute to the rapid dwindling of their populations through laws put in place by humans. This paradoxical involvement of people is precisely where issues arise. 

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With a high cackle and a scold: how an avian alarm system changed our understanding of animal communication

Review written by Natalie Wong (2025, EEB)

The question of what drives animals to cooperate with one other is a compelling one. After all, such behavior contradicts the notion lodged in popular imagination that nature is dominated by ruthless Darwinian battles among feral creatures. Yet, these instances of cooperation serve as a reminder that looking out for others is not limited to the Homo sapiens realm. Several explanations for cooperation in social animals exist, but perhaps the most well-established is kin selection: the idea that organisms can indirectly boost their own fitness by performing actions that help ensure the survival of those with whom they share genetic information.

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Belayer: Modeling Layered Tissues in Spatial Transcriptomics

Review by Tamjeed Azad (COS, G1)

All the marvelous biology we see, from the smallest bugs to the largest trees, is driven by behavior, function, and characteristics of individual cells. The activity of these cells is driven by molecules called proteins, and different cells derive their different characteristics by which specific proteins they use to carry out necessary biological processes. The proteins that are built within cells are determined by which genes of an organism’s DNA are decoded and transcribed into RNA, the blueprint for protein construction. Modern techniques in genetics measure which genes in a tissue are transcribed, in an effort to infer the drivers of such tissues’ biological activity and thus elucidate which functional characteristics are important in a given tissue. Spatially resolved transcriptomics, a subset of these methods, lets biologists and practitioners view which genes are transcribed and to what level (called gene expression) but in a spatial context, making it clear what location within a tissue slice each gene is expressed.

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What tiny worms can teach us about reproductive decline (and how to prevent it)

Review by Abigail Stanton (MOL, G3)

At first glance, Caenorhabditis elegans might not look like much. Measuring in at about 1 mm, these laboratory worms have much simpler biology than your average human. However, this simplicity makes them convenient subjects to study the most basic functions of life because their entire lives from birth to reproduction to death play out over the course of weeks instead of decades. The Murphy Lab in the Department of Molecular Biology at Princeton uses these worms to ask questions about the aging process: what happens at a molecular level that causes us to age, and how can we promote longer, healthier lives? 

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A Bird’s Eye View of the Impacts of Climate Change on Desert Environments

Review written by Anne Larsen (2026, EEB)

There is a widespread misconception that deserts, arid and extreme in climate, are unaffected by climate change. The truth is that deserts are disproportionately impacted by climate change and are projected to see great changes in the distributions of fauna and the behavior of such species due to current warming trends[1]. Though both cold and warm deserts will be affected by these changes, warm deserts have already sustained damage. Indeed, the surprisingly diverse region has suffered much due to climate change, and the ecosystem harbored by this biome constantly lives at its physiological limits[2]. Further changes to these regions would create conditions even more extreme than those to which these species have already adapted, possibly leading to extinction[3].

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Isolation Disorganizes Typical Social Interaction and Whole-Brain Genetic Expression in the Bumblebee

Review written by Adelaide Minerva (PNI, G4) and Rebekah Rashford (PNI, G5)

Throughout the COVID pandemic, many of us were faced with profound levels of social isolation which took a toll on both our mental and physical health. This has been especially detrimental for children, whose brains and social skills are still developing. Normally, social experience in early life plays a crucial role in guiding this development; but what happens when that guidance is no longer present? Disruptions to the early social environment have been seen to negatively impact other social species besides humans, such as mice, fish, and some insects. Studying how social isolation may disrupt the development of these highly social species can provide insight into the neural mechanisms underlying  both typical and aberrant behavior at a level of detail not currently possible in human subjects. Taking advantage of one of these highly social species, Dr. Yan Wang and colleagues in the departments of Ecology & Evolutionary Biology and the Center for Biophysics at Princeton used bumblebees to measure the effects of early life social isolation on behavior, gene expression, and whole-brain neuroanatomy. 

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Early life adversity can induce pathological avoidance behaviors in mice, but males with suppressed neurogenesis may step out of their comfort zones

Review written by Amy Ciceu (NEU, 2024)

Early life adversity, ranging from physical and emotional abuse, neglect, and violence, to poverty and unstable home environments, can have an enduring toll on child development. Some children who experience early life adversity may experience detrimental effects in the moment but develop into adults without pathological behavior. On the other hand, for certain children, the impacts of early life adversity increase the likelihood that they will develop neuropsychiatric disorders as adults. For instance, anxiety disorders are more prevalent amongst survivors of early life adversity compared to the general population. Although diverse in the symptoms they present and the treatments they require, anxiety disorders share one feature in common: heightened levels of anxiety. Normally, anxiety helps us steer clear of dangers. However, if ramped up into overdrive, excessive levels of anxiety can fuel a range of maladaptive behaviors.

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Socioeconomic status effects on human health have evolved with industrialization

Review written by Kimberly Sabsay (QCB, G3)

Socioeconomic status (SES), often simplified as absolute material wealth, is often linked to a variety of human health metrics. At a fundamental level, it makes sense that higher SES likely corresponds with access to better medical services, and in turn, better overall health. Studies have shown that, indeed, higher SES is associated with better human health, but the majority of this data comes from high-income countries (HICs). Despite the growing amount of scientific evidence for the apparent gradients in disease risk and survival explained by access to medical care and other health-related lifestyle factors, we cannot be certain that these trends are universal. Understanding the relationship between SES and health is crucial for policy design and to ensure we make economic decisions that do not negatively impact overall human health. Ultimately, the relationships between SES and health can be used to motivate positive change that benefits all of humanity.

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