Tuesday, July 07, 2009

"Garden," Junk, pt. 2, 360 words

“Yes,” Rosenberg said, slowly, recalling that initial discovery. Not that it had taken much effort to determine. But the popular theory was that the DNA of any mammal-like life found on the planet below would be wildly different from that of Earth mammals, perhaps haploid or even triploid in construction. Rosenberg had just taken it as given that, if the Rhea-life DNA was structured in a ploidal model, then the animal life would be diploid.

The bigger discovery was that Rhea-DNA exhibited ploidy at all, in her mind. Haploid DNA would be too simple for anything of higher order than eusocial, hive-based insect-analogues that reproduced sexually, and triploid DNA implied three biological parents in sexual reproduction (or that one sex provided two sets of chromosomes), which was too complicated. Evolution on Earth had followed a path of least resistance, when it came to adapting to selection pressures and the development of higher-order life. Why would it be any different elsewhere, even on another planet?

But this... She glanced at the screen, which had flickered into a low-power hibernation while she'd waited for Halsey. This blew the question of how many helices were in Rhea-DNA out of the water.

“I want you to look at something,” Rosenberg said. She turned back to the computer and ran a finger along the trackpad to pull it out of hibernation. The screen flickered back to life, and Rosenberg brought the focus onto the sequencer program. It was an inelegant piece of code, designed for the brute work of isolating and scanning the DNA of a tissue sample, and it chewed up a computer's processing power. Compared to the time it took to sequence a DNA sample just two hundred years ago, though, when molecular genetics was coming into its own as a field, the modern sequencer program flew like an eagle sweeping down onto its prey.

Two long strings of data, and the images of spinning DNA helices that summed up the text, were crammed together on the screen. One was clearly a sample of Earth life, with adenine tagged in green, thymine in violet, cytosine in red, and guanine in blue.

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