Tag: science

Gynandromorphs

For 100s of years, naturalists have been documenting gynandromorphs among insects, spiders, lobsters, and birds. More recently, researchers—aided by increasingly sophisticated laboratory tools—have overturned reigning theories of sexual development by studying such hybrids. As has proven true time and again throughout the history of science, the creatures that seem strangest—those that are too odd, too asymmetrical to fit neatly into our presupposed categories—teach us the most about how all living things work. It turns out, for example, that the standard explanation of how a bird becomes male or female is wrong. Scientists came to this realization not by investigating scores of typical birds, but rather by examining a few gynandromorphs. It all started with an odd zebra finch.

Neutron gold

Neutron star collision may have seeded the solar system with gold

In a new study, astronomers have found that a small fraction of all the gold on planet Earth was likely formed in a single, catastrophic, and very weird event: The merger of 2 neutron stars. The material blasted out from the ensuing explosion mixed with the stuff that formed the Sun and planets, and, eventually, us. Literally, you and me.

Amber Millipede

The 3D reconstruction of a 99M-year-old millipede discovered in Burmese amber allowed for the description of an entirely new suborder, and is just one of the many exciting discoveries in Burmese amber. Burmese amber, mostly coming from the Hukawng Valley in Kachin State, northern Myanmar, is valuable not only for understanding of the Myriapoda fossil record and historical biogeography, but also including fantastic fossils of frogs, bone and feathers from theropod wings, a whole bird trapped in amber, and the previously discussed feathered tip of a dinosaur tail.

Beyond Oil Feedstocks

you’d need electrochemical efficiencies of at least 60% and electricity available at 4 cents/kilowatt-hr or better to make these ideas profitable (with the usual 30-year-amortization assumption about the plants themselves). How close are we? Many of the processes are currently in the 40-50% efficiency range, and need further scale-up work: within sight, but not there yet. And renewable electricity costs vary a great deal by region. The best cases are getting down around that figure, though, and continuing to improve. 1 feature of electrochemical synthesis is that it would (as mentioned in the excerpt above) provide a use for the mismatched local excess electrical production that can happen with renewables – it’s storage of energy in chemical bonds as opposed to batteries, flywheels, or what have you. But on the other hand, running a chemical plant 24/7 is by far the most economical way to set things up, so the best solution would be coupling with some steadier source of electricity as well.

Discovering Denisovans

I had long suspected that Denisovans represented a substantial portion of the already-known Chinese fossil record; they just hadn’t been identified. The Xiahe jaw, we hoped, could bridge the gap. The Xiahe mandible is complete enough to now revisit the rich Chinese hominin fossil collection and identify other fossils as Denisovan, even without DNA evidence. I have no doubt that in the future the sequencing of ancient proteins will complement these morphological analyses. But the most extraordinary aspect of our findings is the demonstration that such archaic hominins could successfully live in this challenging high-altitude environment, more than 120 ka before modern H. sapiens settled on the Tibetan Plateau. It seems that a gene variant that helps modern populations on the Tibetan Plateau to adapt to high-altitude hypoxia was inherited from these Denisovans.

Dark Matter Evidence?

While dark matter doesn’t shine or fraternize with known particles, in the right sort of collision these particles could annihilate in a shower of familiar matter and antimatter that would then go out with a puff of gamma rays. A measurement of these offshoots would represent the first evidence of dark matter that wasn’t exclusively gravitational in nature. Yet dark matter wasn’t the only thing that could be generating the excess gamma rays. They could shine from cosmic lighthouses known as millisecond pulsars — magnetically charged neutron stars that make 1000 turns each second. A group of undiscovered pulsars too dim to be picked out individually could be bathing the center of the galaxy in extra gamma rays. Experts express optimism that with these inputs, the current modeling wars could settle down in a matter of years. And now that the gamma ray glow is back on the table, hopes for dark matter look somewhat brighter. “If the galactic center excess is back in the game, potentially we are seeing the first signal of dark matter.”