Transposons: Your DNA that’s on the go

by Francesca Tomasi figures by Olivia Foster Rhoades Argonaut. Idéfix. Flamenco. These words invoke movement: the ancient Greek Argonauts were a band of adventurous sailors famous for their epic quests. Meanwhile, Idéfix is the name of an adventure-loving dog in the French Astérix comic book series. And finally, flamenco conjures images of vivacious dancers. You would think the similarities between Greek mythology, French comic books, and … Continue reading Transposons: Your DNA that’s on the go

Heat waves hurt your brain: the argument for window AC units

As our planet warms, the effects of heat on the human body will become important information. The human body is capable of dealing with heat, but reprieves are needed to allow our systems to rest, else our bodies become over-stressed. This reprieve often comes in the form of night, when temperatures typically  cool. During heat waves, nights remain toasty, and reprieves only exist for those … Continue reading Heat waves hurt your brain: the argument for window AC units

Bacteria snatch up foreign material using specialized arm-like structures

In order to adapt to their environments, it is important that bacteria be able to mix up their genetic code. One way that bacteria do this is by taking up bits of free-floating foreign DNA that can be released by other kinds of bacteria into their environments when they die. This process is called ‘transformation.’ The pieces of DNA can occasionally encode components that make … Continue reading Bacteria snatch up foreign material using specialized arm-like structures

ARIEL: Exploring strange new worlds and boldly observing what no telescope has observed before.

Since the first exoplanet discovery in the 1990s, scientists have learned of the diverse and abundant nature of exoplanets, having now found more than 3700. With such a large and disparate sample set, ESA (European Space Agency) has set its sights on learning how these planets form and what their chemistry is like. A new telescope, or ‘mission’, ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey), has … Continue reading ARIEL: Exploring strange new worlds and boldly observing what no telescope has observed before.


Plants grow in interesting ways. You may have noticed that your houseplants “lean” towards the window, seeking the sunlight. This movement towards light is called phototropism. Tropism is a general term referring to any instance of growth or movement of an organism in response to the environment. Vines display another kind of tropism known as thigmotropism, meaning they respond to touch. In this set of … Continue reading Vines

Colonies 5

The colonies in this image display some of the diversity of pigment production in Pseudomonas aeruginosa. The blue-green colonies contain a pigment called pyocyanin, which is known to be toxic to human cells and helps the bacteria establish a niche during infections. The colonies containing a brown halo produce the brown pigment pyomelanin, which is thought to help the bacteria scavenge for iron, an essential … Continue reading Colonies 5

Colonies 4

To get around, Pseudomonas aeruginosa bacterium use a number of motility strategies, such as twitching and gliding. In this image, we see a special kind of bacterial motility behavior known as swarming, where a mass of bacteria moves collectively across a surface.  This is an example of singled celled bacterial species acting in a multicellular way. For a group of cells to swarm, the bacterium … Continue reading Colonies 4

Colonies 3

It may be hard to believe, but this sea of shiny, donut-shaped colonies are Pseudomonas aeruginosa colonies. These Pseudomonas colonies have a genetic mutation that causes many of the bacteria’s genes to be shut off. The donut-shape of these colonies may indicate a two-step growth phase where the younger cells on the outside edge of the colony grow towards more nutrients while the older cells in … Continue reading Colonies 3

Colonies 1 and 2

No one likes to be in crowded spaces, so when colonies reach a critical cell density, cells within the colony begin to lyse, dramatically changing the architecture of the colony. The colony on the left is a wild-type colony, while the colony on the right is a genetic mutant that exhibits an autolytic phenotype, that is the bacterium’s own enzymes “eat up” its cells. The … Continue reading Colonies 1 and 2