Category: New Research

New Method May Provide Clues To Dinosaur Body Temperature

Scientists have many questions about how the internal condition of dinosaurs (not preserved in fossilized remains) may have influenced the way those creatures lived. One of the conditions in question is whether or not dinosaurs were cold blooded or warm blooded and what were their internal temperatures. But now a team of researchers from the California Institute of Technology believe they have developed a method by which they can identify the internal temperature of dinosaurs based on fossilized teeth. 

Caltech Geochemists Rob Eagle (L) and John Eiler

The researchers, led by postdoctoral researcher Robert Eagle, studied isotopic concentrations in 11 fossilized teeth from sauropods (the long-tailed, long-necked dinosaurs). The teeth were recovered from sites in Tanzania, Wyoming and Oklahoma and belonged to Brachiosaurus and Camarasaurus dinosaurs. 


The method used for this analysis is called a clumped isotope technique. The concentrations of the isotopes carbon-13 and oxygen-18 in bioapatite, a mineral found in teeth and bone. How often these isotopes bond with each other (clump, if you will) hinges on the temperature. The lower the temperature the more the isotopes tend to bond with each other. So, the researchers measured how these isotopes clumped together to determine the environmental (in this instance the internal condition of the dinosaur) temperature. At least, the temperature of the tooth.


The study allowed the researchers to estimate the temperature of Brachiosaurus to 100.8 degrees Fahrenheit and the temperature of Camarasaurus to 96.3 degrees Fahrenheit. This is warmer than living and extinct reptile species (like crocodiles) but is cooler than birds both of which are believed to be modern descendants of the dinosaurs. According to the researchers the measurements are accurate to within one or two degrees.

Drilling a Camarasaurus tooth

Prior to this research, the best way to evaluate the internal temperature of dinosaurs was to infer what would be most likely based on the dinosaur’s behavior and physiology. However, researchers sought a method that would be more specific. That’s not to say the researcher’s new method is infallible. While they have made big claims about it being “bullet proof,” it remains to be seen whether this method is the most accurate and effective. 


The study led the Caltech researchers to conclude that dinosaurs were warm blooded (have an internal mechanism to moderate body temperature), but they warn that the issue is actually more complicated that just temperature readings. Even if the creatures were cold blooded and relied on their environment for warmth, they still could have had very warm bodies. Unfortunately knowing the temperature of the teeth don’t answer all of the remaining questions about dinosaur temperature.


The scientists hope to expand upon this study to include analysis of the teeth of other species of extinct vertebrates, in addition to determining the internal temperatures of small and young dinosaurs that may reveal more about how temperature affected the way these creatures lived. The research paper was published in ScienceExpress. More information (from a press release) is available from Caltech and in the following video (which were both used as sources for this post.) 

(All media courtesy of Caltech)

What Makes A Planet A Planet?

I grew up believing that there were nine planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Then, in 2006 my understanding of the universe was shaken when poor little Pluto was stripped of its classification and labelled just another object in the Kuiper Belt, an area that extends from the orbit of Neptune and contains thousands of icy “objects” with the same consistency as Pluto.

The decision that Pluto was not a planet came in 2006 based on the 2005 discovery of Eris, an object larger than Pluto, in the Kuiper Belt. Pluto and Eris are both considered “dwarf planets.” According to the International Astronomical Union for an object to be a planet it must meet three criteria:

  1. It needs to orbit around the sun (or if part of a different solar system than ours, it needs to orbit around another star)
  2. It needs to have enough gravity to pull itself into a spherical shape
  3. It must be the dominant gravitational body in its orbit (thus any smaller body in its orbit is either consumed or flung away by the object’s gravitational pull – being smaller than Eris, Pluto clearly doesn’t qualify)
Pluto by the Hubble Space Telescope via Wikimedia Commons

But why digress on a five-year old story about a former planet’s rejection? Well, because the issue of what makes something a planet seems like it could again be coming into question. This week the BBC  ran the article “Free-floating planets found with no star in sight” talking about the new discovery of objects in space that are seemingly un-connected to a star. The BBC article is referencing the research “Bound and unbound planets abound” featured in Nature, and as we learned from the Pluto experience, criteria #1 for being classified as a planet is that the object in question needs to orbit a star.

So then what is going on with the new discovery of at least 10 objects the size of Jupiter that don’t orbit a star? The research suggests that objects like this might be so common, they actually outnumber stars 2:1. While the BBC’s article states that researcher are cautious to completely flip our understanding of the universe based on a single study – if true, it would completely flip our understanding of the universe.

The definition of a planet is firmly grounded in the three criteria listed above, so these new objects don’t fit the bill because #1 – orbiting a star is violated. But then, what are they? The answer to that is a little complicated. The BBC’s article doesn’t explain it. So, since I have zero background in astronomy, I did some digging and found Phil Plait’s blog Bad Astronomy for Discover.

According to Plait’s post called “The galaxy may swarm with billions of wandering planets,” the objects talked about in the Nature study either formed like stars or they formed like planets in solar systems (like our own) and got tossed out. Plait favors the latter, saying they are most likely rejects from other solar systems.

He explains that massive planets often form along the outside of a solar system, and then migrate inward toward the center star. This could cause other plants in the path of the migrating planet to undergo changes in their orbit, or even get flung out the solar system completely. It is these planets that get flung out of their solar system by the movement of larger planets that could be the star-less objects featured in the Nature study. The evidence in favor of this theory is the prevalence of large plants that orbit very close to their stars.

So most likely – the objects in question ARE planets, they formed like planets, in a solar system that orbited a star. But, somewhere along the way they got tossed out of their solar system, and thus became free-floating planets.

I’ll be interested to see if there is any kind of distinction as far as name or classification that these rogue planets are given, that identifies that they are different than your typical planet. Lord knows losing Pluto was bad enough, I’m not sure what I’ll do if there is another planetary shake up. Its rough seeing things you learned when you were six get turned on their head. But, it is also incredibly cool how much new information the universe still has to give up. I really love the idea that there could be so many free-floating planets out there waiting to be discovered.

How To: Recycle A Chicken?

Once again I’m using Science Decoded for my long form journalism class. Our assignment this week was to do a post that was under 350 words. I put up short posts all the time, but I decided to use the assignment to go back to my blogging style from last Fall and give a short run-down of newly published research.

Did you know that you can recycle a chicken? Well, recycle part of a chicken at least. Research has previously been proposed to use bio-waste (hair, nails, or in this case chicken feathers) to create plastics. But new research presented at the annual meeting of the American Chemical Society shows that a new mixture using 50% chicken feathers (the largest amount used to date) can actually make the material we use for shopping bags, eating utensils, children’s toys and millions of other objects.

Millions of chicken feathers are discarded in the United States each year, which makes finding a use for them highly worthwhile. Feathers are made of the protein keratin. When combined with the chemical methyl acrylate, the feathers form a strong but relatively light weight plastic substance.

Source: Wikimedia Commons

Typically making plastics requires petroleum derived products like polyethylene and polypropylene. The feather-methyl acrylate combination could reduce the need for petroleum derived plastic products, which would be environmentally beneficial. Without petroleum the plastics would be more degradable and sustainable.

This research, led by Yiqi Yang of the University of Nebraska was conducted on a small scale. Until the new feather compound is tested on a large scale for ease of production and energy required for production it is unclear if it could realistically be used to manufacture commercial plastic products.

This research is exciting because it is essentially a form of recycling. The chicken feathers are just being discarded anyway, so if they can be used to make plastics that are more environmentally friendly not only will we benefit from finding a use for the feathers, we’ll also benefit from having a more sustainable plastic.

The big BUT in this article is that it needs further testing before it can be implemented. It is important with research like this to remember that a scientific find isn’t a definite. Just because something works on a small scale, doesn’t mean that it will work on a large scale. So even though the finding is exciting, it doesn’t mean that it will actually be implemented.

History Remains a Mystery: DNA Can’t Confirm Remains Are Amelia Earhart

I use Science Decoded for class and have assignments that require me to post in certain ways. This week I’m ATTEMPTING to write in a diamond structure (writers will know it but that means really specific- big issue- really specific.) I’m going to try to do so by tackling Amelia Earhart and the role of DNA analysis in identifying her possible remains, a subject I previously mentioned in the post What Happened to Amelia Earhart?

Today she is the topic of book reports, the namesake of streets, schools and scholarships, and even the subject of a major motion picture starring actress Hilary Swank. But in 1937 when she decided to fly around the world, Amelia Earhart – famous though she was – was also something unheard of at the time. She was a woman shattering convention – simply because she wanted to.
Amelia Earhart broke her first world record at the age of 24 on October 22, 1922 when she flew her airplane to an altitude of 14,000ft. The highest altitude then recorded for a female pilot. By April 8, 1931 she would beat her own record soaring to 18,415ft. She set four records for speed from 1930-1933, and in 1932 she was the first woman to fly solo across the Atlantic Ocean, five years to the day after Charles Lindberg first accomplished the feat. She wrote a book about the trip called “For the Fun of It.”
Earhart became a champion for women’s rights by being an outspoken female figure in a male dominated field. In 1932 she helped form, and was elected president of the Ninety Nines a club for women aviators.

According to the website operated by the estate of the famous aviator, Amelia Earhart is quoted as having said, “One of my favorite phobias is that girls, especially those whose tastes aren’t routine, often don’t get a fair break. It has come down through the generations, an inheritance of age-old customs which produced the corollary that women are bred to timidity.”

Source: Wikimedia Commons
Earhart was the first person to fly solo from Los Angeles to Mexico City, the first person to fly from Mexico City to Newark nonstop, and the first person to fly across the Red Sea to India. Not just the first woman. She was the first PERSON to complete these milestone trips.

Having accomplished all of this it is no surprise that on June 1, 1937 when she was 39-years-old Earhart set out to become the first woman to fly around the world. She almost succeeded. On June 29th, Earhart and navigator Fred Noonan arrived in Lae, New Guinea with only 7,000 miles of the trip left. On July 2nd Earhart and Noonan took off for their next checkpoint at Howland Island. 
It is here that the story of a strong female aviator, a role model for men and women alike becomes a mystery. She was sucked into the vortex of the Bermuda triangle. She flew to Rio to live a life of secrecy. She was abducted by aliens. Although the theories about why Earhart never arrived at Howland Island are many, truly no one knows what happened to her, Noonan, or their twin engine Lockheed Electra airplane. Although the most likely scenario is that Earhart and Noonan were unable to find Howland Island and then ran out of fuel.

With clouds obscuring the stars, Noonan’s ability to navigate would have been heavily compromised. The failure of their radio transmissions would have left Earhart and Noonan unable to ask for help. Landing in the ocean or on one of the South Pacific’s islands may or may not have killed the aviator. She was declared dead, but some say she could have survived the landing and lived for awhile as a castaway. This theory was buoyed in 2010 by the discovery of three bone fragments that might be a human finger on Nikumaroro (formerly known as Gardner Island) in the Republic of Kiribati.

It was on Nikumaroro in 1940 that a British Naval officer found 13 bones including a skull believed to belong to a castaway. The bones were sent to Fiji for analysis where they were later misplaced. A connection was never made to Earhart because at the time the bones were analyzed and believed to belong to a man. American officials were never officially notified of the discovery.


The International Group for Historic Aircraft Recovery (TIGHAR) took up the mystery of what happened to Earhart and Noonan and the possibility that the 1940 Nikumaroro bones were either the aviator or her navigator in 1988. An analysis of records from Fiji conducted by TIGHAR forensic anthropologists based on new computerized technology indicate that the initial analysis was wrong and the remains belonged to a white female.
TIGHAR conducted new searches of the island in 2001, 2007 and 2010. The search in 2010 turned up the three bone fragments, reportedly in the same area that the original 13 misplaced bones were found. TIGHAR recruited the help of Cecil Lewis of the University of Oklahoma’s Molecular Anthropology Laboratories to analyze the bone fragments. Last week TIGHAR announced that Lewis’ findings were inconclusive. It is possible that the bones are a human finger bone, but bones could also belong to a sea turtle. Other organisms like birds and fish have been ruled out due to the structure of the bone.
Nikumaroro Map. Source: Flickr.

The initial test for the presence of human mitochondrial DNA conducted by Lewis was positive, but subsequent tests did not replicate that result. Because the process of extracting DNA damages the bone, further attempts to determine the bone’s origin would use up the rest of the sample. Doing so would make independent replication – a crucial part of the scientific process in which other scientists conduct the same experiment to make sure that the results are valid – an impossibility.

A mitochondrial DNA profile on Earhart has been compiled from a female relative. Mitochondria are an organelle – a small part of a cell. Mitochondria are involved in creating energy to power the cell. Unlike the rest of the cell, mitochondria contain DNA that is directly passed between mother and child, meaning that it is the same for all individuals on the maternal side of the family lineage.
TIGHAR has decided to shelve the DNA testing of the 2010 Nikumaroro bone fragments to ensure that in the future when DNA analysis technology improves to the point where less material is needed to discover if the bones are human (and if they are Earhart’s) there will still be enough of the bones left to test. But, when the bone is able to be tested for human DNA, the mitochondrial DNA profile of Earhart will be used to confirm if the bones are hers.
Other artifacts recovered from the Nikumaroro site (including what may be fecal matter, a freckle cream jar, and evidence of meals being cooked) are still being analyzed for direct evidence of Earhart or Noonan. Another expedition to Nikumaroro is scheduled for the summer of 2012 – to mark the 75th anniversary of Earhart’s flight and disappearance. The new expedition will focus on finding the remains of her Lockheed Electra, believed to be deep down on the slope of the reef on the Island’s west end.
The identification of Earhart’s remains (if they are hers) would be a triumph of scientific technology. As her story becomes intertwined with science, it becomes ever more ironic that Earhart didn’t view the information gathered from her flights as science. “I lay no claim to advancing scientific data other than advancing flying knowledge,” she said. “I can only say that I do it because I want to.”
If Earhart has a scientific legacy it is not to be found in her bones. Earhart believed women should never stop trying to excel in fields dominated by men. She busted the boys club of aviation, and paved the way for women to do the same in other fields. Female scientists who have broken into their own boys club, and penetrated the historically male dominated research fields embody Earhart’s determination to succeed.
Whether or not science will one day be able to tell if Earhart met her end on Nikumaroro Island, her legacy to science, and all of society, is in encouraging women to break with convention.
“Now and then women should do for themselves what men have already done – occasionally what men have not done – thereby establishing themselves as persons, and perhaps encouraging other women toward greater independence of through and action. Some such consideration was a contributing reason for my wanting to do what I so much wanted to do.”

Thunder Thighs

Perusing the BBC today, the headline “Dinosaur had thunder thighs” leapt off the page and made me laugh, so I couldn’t help but share it here. Coming from a background where I was in a sorority as an undergraduate, I can assure you that when someone dropped the term “thunder thighs” they were not talking about dinosaur muscles. But this is a case of scientists having a sense of humor, using the term to name a new dinosaur species.

The species is a sauropod, a type of dinosaur characterized by their long necks and tails. According to the researchers, the fossilized hip bone is larger than the hips in other similar species. This along with the unique shape of the hip socket which shows a large space for muscles to connect, led the researchers to conclude that B. mcintoshi would have had powerful legs capable of delivering strong kicks.
A representation of some long necked sauropods.
Source: Wikimedia Commons

The dinosaur species is technically called Brontomerus mcintoshi from the Greek bronto for thunder and meros for thigh. Leading to the common name, thunder thighs. The researchers from University College London who discovered the significance of the fossilized remains (which are fragmentary, but enough to draw conclusions) named the species the way they did because it would have had extremely powerful and muscular legs.

The fossils date back to the Early Cretaceous Period, and are estimated at 110 million years old. The finds were uncovered in the Hotel Mesa Quarry in Grand County, Utah. The site is known to have been scoured by fossil hunters, leaving researchers to speculate whether other interesting finds (like thunder thighs) may have been carried off to private collections.

I like the BBC’s coverage of this scientific find so much, because they had fun with the name of the species, but not so much as to dilute the importance of the find. The article is detailed and (I think) does a good job of explaining what is significant about the species and the location where it was uncovered. If nothing else, the title alone is clearly a success because it got me to read the entire article.

It is important to note that the bones were discovered in the 1990’s and stored at the Oklahoma Museum of Natural History, but the significance of the hip bone wasn’t discovered until Dr. Mike Taylor from University College London evaluated them in 2007. Results of this study were published recently in the journal Acta Palaeontologica Polonica.