BioQuakes

AP Biology class blog for discussing current research in Biology

Author: fishinthesie

Can Stress Affect Pregnancies in Later Generations?

We all know stress isn’t always a good thing, but it could be important to especially avoid it at certain points in one’s life. Recently researchers from the University of Lethbridge in Canada investigated the effects of stress on pregnancies and how it can influence pre-term births. It is already known that pre-term births them selves lead to health issues later in life, but there were some new discoveries involving epigenetics.

 

Epigenetic_mechanisms

 

These researchers studied the length pregnancies of rats, due to the generally small amounts of variation between them, and found something intriguing. They carried out the experiment by first splitting the first generation of rats into “stressed” and “not stressed” groups. What they found was that the daughters of stressed rats had a shorter pregnancy than the daughters of not stressed rats.

This trend continued into the granddaughters of the rats. They also displayed high levels of glucose than the control group, and they weighed less. The stress also compounded, or increased, through generations.

This can all translate into human pregnancies. The researchers believe that the epigenetic changes in the rats is due to microRNA (miRNA) – non-coding RNA molecules that play a role in regulating gene expression. They bind to complementary mRNAs and prevent them from being translated. This is different than what is usual belief with epigenetics which is that epigenomes are affected by DNA methylation of the nucleotide base pairs. Metz, a scientist working on this research states that microRNAs “are important biomarkers of human disease, can be generated by experiences and inherited across generations. We have now shown that maternal stress can generate miRNA modifications with effects across several generations.”

It is very similar to the information found with the generational epigenetic effects of famine in the “Ghost in Our Genes” video that we watched in class.

This research can help determine pre-term births and the causalities that can come along with them. While the research is still not the whole picture, it is another step towards understanding our genetics.

 

Smallest Komodo Dragon Out There.

Most everyone knows that Komodo Dragons are the largest lizards on the planet. Surprisingly, humans have only known about these lizards for about 100 years. But thats nothing compared to the newest discovery of a very very small relative of the Komodo dragon. (original article)

These lizards, about the length of a human hand and very skinny, are about as small as the Komodo’s are big. They are even smaller than the pygmy goanna (the short-tailed monitor, V. brevicauda), which, until now, was believed to be the smallest relative of the Komodo Dragon. These new tiny dragons are shorter, thinner, and more boldly colored than the pygmy goanna. It is believed that around the same time chimpanzees and humans begun to separately evolve (between six million and seven million years ago) the pygmy and the newest lizard edition began to evolve separately. Gillenibaumann_01

These little lizards were discovered in Australia, the home of their slightly pygmy goanna larger relatives. Some females can now be seen in the Western Australian Museum in Welshpool. These lizards have yet to be named, but have been nicknamed “Pokey”.

It’s the little discoveries like these that make us realize how much more we still have to learn and discover about our planet. The planet is so vast that in our relatively short period of time here, there is no way we have a full understanding of the creatures we share the earth with!

Too Hot to Handle?

Climate scientist Axel Timmermann has recently stated that “this summer has seen the highest global mean sea surface temperatures ever recorded since their systematic measuring started. Temperatures even exceed those of the record-breaking 1998 El Niño year.” Timmermann has been studying the global climate system and according to his studies, the “Global Warming Hiatus” came to an end in April 2014.

He says that the North Pacific has been the cause of most of the global ocean warming, whose temperature has risen far above any recorded temperatures, has shifted hurricane tracks, and has changed trade winds. There has even been coral bleaching in the waters surrounding the Hawaiian Islands. Apparently, this began in January 2014 when the sea-surface temperatures suddenly began to rise at an unusual rate. Then in April and May, the warm waters of the western Pacific spread to the eastern Pacific, releasing large amounts of heat into the atmosphere. This heat hadn’t been in the atmosphere for nearly a decade.

Ocean Temperatures

(Sea Surface Temperatures 2003-2011)

Timmermann says that “record-breaking greenhouse gas concentrations and anomalously weak North Pacific summer trade winds, which usually cool the ocean surface, have contributed further to the rise in sea surface temperatures.” These warm temperatures have been spreading all the way to the Gulf of Alaska.

As this 14-year break in the ocean warming comes to an end, more questions come to the surface: What can we do? What other effects will this have on other environments? Will there be another hiatus?

Certainly this is just another piece in the puzzle of the larger global warming issue, and if it isn’t reversible, how can we stop other similar issues?

Throw Away Those Old Dinosaur Toys, Theres A New Kind of Dino in Town

Macronaria_scrubbed_enh

 

Growing up, dinosaurs were always cold-blooded, reptile-like creatures, right? Well recent research has put that theory to rest. Dinosaurs may have been much more warm blooded, than we previously thought.

Originally, scientists thought that dinosaurs were slow, low-energy creatures that only required heat from sunlight to go about their daily lives. This thought changed drastically in the 1960s when research showed that dinosaurs were much more like birds in the sense that they actually use lots of energy and internally regulate their body temperature. These theories created our super fast Jurassic Park dinosaurs.

Recently, though, paleoecologist John Grady stated that it isn’t quite so black and white for these animals. Grady got together with a team of colleagues and calculated the growth rate of an animal in relation to it’s energy use and put it on a scale ranging from animals such as crocodiles, slow-moving and low metabolism, to ostriches, fast moving and high metabolism. From there, the research team was able to estimate where on the scale dinosaurs fell, and to their surprise, it was right in the middle.

It turns out that dinosaurs may have had metabolisms similar to that of a great white shark or tuna. And while it may be hard to believe that dinosaurs are similar to tuna, these findings will help scientists better understand dinosaurs especially things such as how they hunted and why they grew to such large sizes!

Our view of what kind of creatures dinosaurs were could change completely in the next few years! Discoveries like these will help us understand how they lived on the planet so long, and possibly help us understand how to better the longevity of the human race.

 

Powered by WordPress & Theme by Anders Norén

Skip to toolbar