A Species Arises: Ancient Reef-Building Coral Duplicates Genome in Response to Changing Environmental Conditions

By: Wafae El-Arar, Brandon Haffner, Grace Pickering, and Andrew Williams (Stonehill College, BIO323: Evolution, Spring 2020)

Due to rising sea water temperatures, a life-sustaining ecosystem in our oceans is under threat. Coral reefs are dying at a daunting rate, and climate change threatens many species that rely on the reefs. The coral species that are the architects of the reefs, such as Astreopora, or star coral, and Acropora, or stony coral, are some of many under threat. Researchers Yafei Mao and Noriyuki Satoh have been studying these species in order to determine their evolutionary history, and how more information on their evolutionary history can help to better understand coral reef biodiversity and support conservation efforts.  

Acropora donei, by K. Osborne <https://commons.wikimedia.org/wiki/File:Acropora_donei,_Masig.jpg>
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What’s All the Buzz About?

By: Kelsey DaSilva, Lauren Quintiliani, Cara Reynolds, and Mia Romano (Stonehill College, BIO323: Evolution, Spring 2020)

Welcome to the blog “What’s All the Buzz About,” serving you your daily buzz so prepare to be(e) amazed. This article examined honey bee queens of the species scientifically known as Apis mellifera. The common name for the species is western honey bee, and it is the most common honey bee species in the world. These bees are social insects, which means they exhibit a high level of societal organization. This is seen in their overlapping generations within a colony of adults, division of labor, and in the way broods, or groups of bees, work together. These characteristics make honey bees a model organism for studying social evolution. The article aimed to explore differences in observed egg size and the cause of egg size variation. Plasticity plays a large role here and is defined as the ability of an organism to be flexible and to change in various aspects based on factors in their environment. Plasticity occurs in organisms for evolutionary beneficial reasons. Understanding plasticity and variability in genes, specifically seen in the egg size of honey bees, is important because it serves as a model to understand life on earth, it can increase fitness, generate novelty, and facilitate evolution. This article helps to further understand evolution in a social context and provides a practical application of plasticity.

Western honey bee (Apis mellifera), by A. Trepte <https://commons.wikimedia.org/wiki/File:Apis_mellifera_Western_honey_bee.jpg>
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A Small Snail with Big Influence

By: Claire Shamber, Lauren O’Regan, Julia Nuzzo, and Julia Tawil (Stonehill College, BIO323: Evolution, Spring 2020)

Periwinkle is not just a color; it is also an organism! Flat periwinkles are small sea snails that live throughout the northern shores of the Atlantic Ocean. Researchers have been interested in periwinkles because of their large dispersal across different shores and their potential to provide information about the intertidal zone. The intertidal zone is the area where the ocean meets the shoreline between low and high tides. This environment is subject to ecological speciation, meaning that the varying conditions of the intertidal zone can create differences between species. Speciation is the process of a single species splitting into two separate distinct species. Periwinkles offer a good look into how we determine whether two populations should be considered as their own species.

Littorina obtusata, by H. Zell <https://commons.wikimedia.org/wiki/File:Littorina_obtusata_01.jpg>
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Sexual Selection: Big-brain vs. Small-brain

Gianna Amatucci, Nick Mulvey, Caitlin Welsh, & Cayleigh Shufelt (Stonehill College, BIO 323 Evolution, Fall 2019)

Predominantly residing in the tropics of South America, guppies are small and colorful freshwater fish. They are omnivorous animals, primarily consuming algae and brine shrimp. Unfortunately, guppies are preyed upon by a number of larger creatures, including birds, larger fish and mammals. While constantly having to avoid such predators, guppies are always in search of a suitable mate to spread their gene pools to future offspring. Alberto Corral-López and colleagues studied how predation pressure, in addition to cognitive ability and brain size, affected sexual behavior and sexual selection in guppies. The actions of both large-brained and small-brained female and male guppies were observed by Corral-López in order to study this phenomenon.

Domestic male guppy in an S-curve mating display. Image credit: “older guy 22feb08” by Alice Chaos is licensed under CC BY-NC-SA 2.0
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Salty Cetaceans

By: Emma Foster, Ana Alcantara, Apsara Gurung (Stonehill College, BIO 323 Evolution, Fall 2019) 

While humans can taste a variety of flavors, this is not true for all mammals. Researches Dr. Kangli Zhu and other collaborators recently published the research article “The loss of taste genes in cetaceans,” and found that they are only able to detect one out of five sensations of taste. These tastes include sweet, salty, bitter, umami, and sour, but they can only taste salt. Taste is important to mammal adaptations, particularly in cetaceans, which are a group of organisms including whales, dolphins, and porpoises. Umami and sweet taste sensations are important for finding and eating nutritious protein- and energy-rich foods. Salt is also an attractive taste and helps animals maintain sodium levels. Bitter taste is beneficial for aversion to prevent ingestion of toxic or harmful foods. Sour taste also prevents the ingestion of potentially unripe or decayed foods.  

Bottlenose Dolphin
Image credit: https://ccsearch.creativecommons.org/photos/2a8c0f53-d8c8-41e8-9cae-5f8ff1948cce “A little smile for you” by San Diego Shooter is licensed under CC BY-NC-ND 2.0
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How to break a sweat

By: Adam Ziegler, Matthew Papp, Shivam Gandhi, Nikolas Steege, Bio323 Evolution, Fall 2019, Stonehill College

Let’s face it, we all sweat. Despite sweat being such a common and prominent aspect of everyday life, not many people understand what causes sweating, or why not all mammals sweat. A recent paper explored the difference in human sweat compared to other primates from compiled data sets across three phylogenetic models. The research focused on the two glands that are primarily involved in sweating, the apocrine and eccrine glands. By combining glycogen concentration, climate, and distribution of glands, the authors were able to predict the eccrine gland ancestral relationship. The results show exactly how humans have come to evolve the current gland distribution and offer a previously unstudied insight into our ancestors. 

Demonstration of Sweat. Image credit:  https://en.wikipedia.org/wiki/Perspiration#/media/File:Demonstration_of_Sweat.jpg by Dogbertio 14 is licensed under CC BY 3.0
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The Wonderful Venus Flytrap: Marginal Spikes Form a “Horrid Prison” for Moderate-Sized Insect

By: Daniel Bender, Thomas Dickey, Laryssa Kalbfus, and Emily Langmeyer (Stonehill College, BIO323: Evolution, Spring 2019)

The American Naturalist article, Testing Darwin’s Hypothesis about the Wonderful Venus Flytrap: Marginal Spikes Form a “Horrid Prison” for Moderate-Sized Insect Prey, by Davis et al. (2019) is a set of field observations and lab experiments in support of the hypothesis that marginal spikes increase the success rate of prey capture for medium-sized insects in carnivorous plants. Marginal spikes are the spikes along the edge of a Venus flytrap. As a Venus flytrap closes on its prey, these spikes create an enclosed cage-like structure securing it in place. Darwin theorized that very small insects can slip through the spaces between spikes for escape and very large insects are able to overpower the plant’s snap trap and break free, but moderate-sized insects will be trapped in a “horrid prison” should they find themselves captured. Davis et al. were able to test their hypothesis by measuring prey capture efficiency on plants with marginal spikes and with the marginal spikes removed for different sized crickets. They were able to collect these necessary data sets by performing field data collection of wild plants, a controlled laboratory experiment, and a semi-natural experiment.

Venus flytrap
The trap of a Venus flytrap, showing trigger hairs and marginal spikes. Photo by Noah Elhardt.

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Turtle Neck Evolution

By: Taylor Auletto, Nick Botelho, Jeremy Breen, and Rebecca Johnson (Stonehill College, BIO323: Evolution, Spring 2019)

The neck is a seriously underappreciated part of the body of most organisms. Think about it: what if you didn’t have a neck? Or, what if you were incapable of moving your neck? Weird, huh? The proper development and functioning of a neck are essential to survival for many species. This is especially true for turtles. Turtles have the unique ability to retract their neck into their shell when necessary; without this ability, they would be highly susceptible to predators and other such dangers. As such, researchers Christine Böhmer and Ingmar Werneburg wanted to investigate the way the cervical vertebral (CV) column appears across multiple extinct and living turtle taxa for the first time. The cervical vertebral column is essentially composed of segments of the skeleton that make up the neck. Turtles have 8 (referred to as CV1-CV8) of these segments. What’s more, these segments have been conserved through evolution for millions of years. What we already know, though, is that there are specializations in the CV column that are different (i.e., specialized) in different groups of turtles, depending on the method by which they retract their necks. These differences are known to be due to differences in how Hox genes have been modified through evolution. Hox genes are genes that are involved in the body plan of all organisms. Böhmer and Werneburg state that their work ultimately aims to understand how evolution has worked to create the differences in CV columns that we can see today.

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Telomere Length and Life Spans in Starlings

By: Maggie Diehl, Michaela Duffy, and Bryanna Norden (Stonehill College, BIO323: Evolution, Spring 2019)

When we hear the word “aging”, the first images that pop into our minds are usually those of wrinkled skin and gray hair. Although these are common visual characteristics of aging in humans (and other animals), we often fail to recognize the biological processes behind these physical features. Just as our bodies grow old and lose efficiency, our cells lose their ability to grow and divide properly. The process of the gradual deterioration of function of cells is also known as senescence, which is currently a popular topic in evolutionary biology. For many years, scientists have proposed theories to explain the inevitable struggle of aging. Likewise, they have pondered whether conditions during early development play a role in the longevity of one’s life. To examine this possibility, researchers in previous studies have used telomere length as a predictor of survival. Simply put, telomeres are noncoding DNA regions on the ends of eukaryotic chromosomes. They serve as protectors, preventing unwanted deterioration or fusion with surrounding chromosomes. Additionally, they maintain chromosome stability and serve as “mitotic clocks”, shortening (in length) with each round of cell division. When telomeres shorten to almost nothing, coding DNA is exposed and damaged, resulting in cells failing to function properly. The rate at which these vital “chromosome caps” shorten may be accelerated by various environmental stressors in early life, leading to a faster accumulation of senescent cells (which cannot replicate) and an overall shorter lifespan.

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