Three Science Ghost Stories of 2015 (Halloween special)
This is not your typical Halloween-themed article. There are no pumpkins, zombies, or bats here. Instead, read on for a taste of this year’s (unexpected) “ghost” stories in astrophysics, science policy, and evolution.
- The ghost of a dying star
European Southern Observatory (ESO) presents an image of a mysterious bubble in space. This bubble is called a planetary nebula, which is formed by remnants of a dying star.
In the image, the nebula ESO 378-1, nicknamed Southern Owl Nebula, displays an eerie glow with a diameter of 4 light-years (more than 5000 times longer than the distance between the Sun and Pluto!).
A planetary nebula is produced by the diffusing gas that is ejected by the dying star forming its center. A nebula is a short-lived phenomenon – relatively speaking, with a cosmic scope in mind! – and lasts only for a few tens of thousands of years. (Stars, in comparison, typically live for several billion years.) The gassy orb eventually fades away as the star is depleted and the gas diffuses out into oblivion.
The Sun in our solar system will eventually produce a planetary nebula, some billion years into the future. (Plenty of time to plan for space travel!)
Planetary nebulae are important for the chemical enrichment and recycling in space, making elements crucial to life, such as carbon and nitrogen, available again for the next new stars and planets. As astronomer Carl Sagan has said, “We are made of star stuff.”
The image is provided by the ESO Cosmic Gems program, where more stunning cosmic images await to feast your eyes!
- Medical ghostwriting: pushing for stricter policy
Pharmaceutical and medical device industries often hire writers to prepare clinical trial reports, then, seek academic professionals who are not involved in the study to appear as guest authors.
This so-called ghostwriting in medical literature, where industry sponsors publications and borrows names of academic experts to lend false respectability and credibility, could be especially problematic, when distorted or biased data are included or marketing messages are concealed within, with no indications of clear author contributions.
“Guest authorship is a disturbing violation of academic integrity standards, which form the basis of scientific reliability.” Law experts from the Faculties of Law and Medicine at University of Toronto attacks the practice in their report, arguing that not enough measures are being taken to deter ghostwriting, despite ethical and legal concerns, especially in industry-controlled research. They propose that new policy should impose legal liability on the guest authors to curb such practice.
“We argue that a guest author’s claim for credit of an article written by someone else constitutes legal fraud, and may give rise to claims that could be pursued in a class action based on the Racketeer Influenced and Corrupt Organizations Act [RICO],” the experts state in the report.
The article is published in PLOS Medicine and is freely available.
- What black ghost knifefish and Persian carpet flatworm share in common
Our aquatic systems harbor myriads of diverse groups of organisms, but most of them share the same key trait for survival: underwater agility. Aquatic creatures have evolved in various ways to accomplish this feat, resulting in a wide range of appearances that we’ve come to admire.
Although many groups of organisms look drastically different from one another, they share similar mechanism of swimming. For example, the black ghost knifefish looks utterly different from the Persian carpet flatworm or the cuttlefish, but the three all have arrived at the same solution for optimizing speed, and they rely on the same type of swimming method: median/paired fin propulsion.
This is an example of convergent evolution, describing a process in which distinct groups of animals independently arrive at the same solution for survival. (In yet another example, both birds and bats have wings that share the same function, but they developed completely separately.)
“Why do you see the same traits, such as the camera-lens eye or wings, in animals that are so different and have no common ancestor with that trait?” wondered Malcolm MacIver, a researcher at McCormick School of Engineering and Applied Science, Northwestern University.
To find out, he led a study comparing median/paired fin swimmers from eight different aquatic animal groups.
Median/paired fin swimmers use their pectoral (side) fins in rippling or oscillating (like a pendulum) motions to swim.
After quantifying the mechanical basis of these distinct-looking swimmers, the team found that the ratio of the undulating and oscillating motions of the fins were always very similar across all the eight groups. The researchers conclude that this is the optimum ratio for speed in this particular swimming method.
In answer to the research question above, MacIver replies, “It is because there is a finite number of ways to really do something well. In our study, we have quantified how an unusual group of swimming animals optimizes force and, therefore, speed.”
The findings would help our understanding of evolution and also help us develop underwater vehicles with higher agility.
The study is published in PLOS Biology and is freely available.
I hope you enjoyed the selection of “ghost” stories in science from this year thus far.
Happy Halloween!! 🙂