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Post by Deleted on Aug 6, 2021 13:09:17 GMT -5
Something I thought was interesting in the video is that they touch on one of the hypotheses that primordial black holes could explain the composition of dark matter (one of many hypotheses of course). The concept that they came into existence shortly after the Big Bang is certainly fascinating, though it's not proven they exist and a number of scientists believe there may be significant limits to how much they could actually represent the amount of dark matter we believe to exist from the various articles I've read. Again, just one candidate amongst many in the broader and always intriguing quest to solve the mystery of dark matter.
The video also touched on "quasi-stars" which are likewise a fascinating hypothesis of objects that may have existed during the early days of the universe and were much larger than our modern stars. Instead of being powered by fusion at their core, the energy would come from matter falling into a black hole at the core. The idea is that the early protostars could be so large, that when the core collapsed into a black hole, the outer layers were large enough not to get blown away like in a modern supernova nor fully collapse themselves initially. Eventually they would cool and finally collapse into massive black holes, which is a proposed explanation how blacks holes of that size could exist today. The chart below shows the hypothetical scale of one compared to the largest known star today (and look how the diameter clears the orbit of Neptune!):  |
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Post by Roquefort Raider on Aug 6, 2021 14:04:39 GMT -5
The existence of multiple small black holes could help explain a lot of mysteries!  |
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Post by Deleted on Aug 6, 2021 14:11:24 GMT -5
Laundry is at the heart of all great physics:
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Post by Deleted on Aug 7, 2021 8:11:19 GMT -5
I feel like high school era Peter Parker asking this question, but anybody else here into slime molds? I recently picked up this DVD called NOVA: The Secret Mind of Slime and it's really fascinating (teaser video below). They do not have brains/nervous systems but, to quote the description, "can navigate mazes, choose between foods, and create efficient networks", and it's amazing to watch time-lapse video of these activities in motion.
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Post by Roquefort Raider on Aug 7, 2021 9:00:37 GMT -5
Back when I worked in the U.S, the lab next to ours was working on Dictyostelium. I wasn't really into slime molds, but was impressed by the way Dicty could transition from a mobile slug-like form to a fruiting body. Colonial organisms are particularly interesting to me because they may inform us on how the first multicellular creatures evolved. Siphonophores are also pretty cool in that regard.
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Post by Deleted on Aug 7, 2021 9:09:17 GMT -5
Back when I worked in the U.S, the lab next to ours was working on Dictyostelium. I wasn't really into slime molds, but was impressed by the way Dicty could transition from a mobile slug-like form to a fruiting body. Colonial organisms are particularly interesting to me because they may inform us on how the first multicellular creatures evolved. Siphonophores are also pretty cool in that regard. Thank you, that gives me some extra reading/watching to do this weekend! I just found a short video on siphonophores and am already intrigued (as well as getting a better overall overview of colonial organisms). |
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Post by berkley on Aug 12, 2021 15:43:20 GMT -5
Back when I worked in the U.S, the lab next to ours was working on Dictyostelium. I wasn't really into slime molds, but was impressed by the way Dicty could transition from a mobile slug-like form to a fruiting body. Colonial organisms are particularly interesting to me because they may inform us on how the first multicellular creatures evolved. Siphonophores are also pretty cool in that regard.
There's a good book called Emergence that goes into slime mold behaviour quite a bit, though IIRC it's only one of several examples the author uses to illustrate the concept referred to in the title.
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Confessor
CCF Mod Squad
Not Bucky O'Hare!
Posts: 10,202 
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Post by Confessor on Aug 13, 2021 6:42:06 GMT -5
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Post by Roquefort Raider on Sept 17, 2021 11:47:02 GMT -5
I just learned that armadillos always give birth to identical quadruplets.
Nature is so cool.
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Post by Roquefort Raider on Sept 24, 2021 11:03:45 GMT -5
I just read in Beth Shapiro's How to clone a mammoth that the American chestnut tree had been genetically modified so it would resist the chestnut blight that essentially wiped it out a century ago. Chestnuts used to be everywhere in Appalachia and provided an ample harvest of nuts and high-quality wood that didn't rot, and their loss was an ecological tragedy that's hard to comprehend. The entire environment was radically altered.
The modification is rather simple : a gene for oxalate oxidase (found in other plants, so it's not as if it's a Martian gene or anything) has been added to the chestnut, and that reduces the amount of oxalic acid that the fungus uses to damage trees. Currently the OxO trees are being crossed with wild chestnuts trees to increase the genetic diversity of the resistant trees, in the hope of recreating our ancient chestnut tree forests. The USDA, EPA and FDA are all evaluating the possibility of using these trees to recreate the forests of yore.
Wanting to learn more, I googled the subject... and was dismayed to see that most results I got were from so-called "green" websites who consider that this project is akin to force-feeding Agent Orange to babies.
Granted, as a biologist I may have a skewed opinion... but such a systematic anti-GMO stance is just... nuts (pun unintended). I'm all for being careful when tampering with a species' genes, but mutants appear all the time. Plus, I'm way more comfortable with a new strain that was developed by adding one particular gene in one particular spot than with a new strain that was generated by randomly crossing previous strains or scrambling genomes at random using radiation! At least with targeted mutation we know what we're getting.
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Post by thwhtguardian on Sept 24, 2021 15:28:01 GMT -5
I just read in Beth Shapiro's How to clone a mammoth that the American chestnut tree had been genetically modified so it would resist the chestnut blight that essentially wiped it out a century ago. Chestnuts used to be everywhere in Appalachia and provided an ample harvest of nuts and high-quality wood that didn't rot, and their loss was an ecological tragedy that's hard to comprehend. The entire environment was radically altered. The modification is rather simple : a gene for oxalate oxidase (found in other plants, so it's not as if it's a Martian gene or anything) has been added to the chestnut, and that reduces the amount of oxalic acid that the fungus uses to damage trees. Currently the OxO trees are being crossed with wild chestnuts trees to increase the genetic diversity of the resistant trees, in the hope of recreating our ancient chestnut tree forests. The USDA, EPA and FDA are all evaluating the possibility of using these trees to recreate the forests of yore. Wanting to learn more, I googled the subject... and was dismayed to see that most results I got were from so-called "green" websites who consider that this project is akin to force-feeding Agent Orange to babies. Granted, as a biologist I may have a skewed opinion... but such a systematic ant-GMO stance is just... nuts (pun unintended). I'm all for being careful when tampering with a species gene, but mutants appear all the time. Plus, I'm way more comfortable with a new strain that was developed by adding one particular gene in one particular spot than with a new strain that was generated by randomly crossing previous strains or scrambling genomes at random using radiation! At least with targeted mutation we know what we're getting. That book was fantastic, I make a habbit of checking out the Church lab site periodically to see any updates on the process. |
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Post by Mister Spaceman on Oct 24, 2021 10:20:46 GMT -5
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Post by Roquefort Raider on Oct 24, 2021 17:27:30 GMT -5
I invoke Betteridge's law!  |
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Post by berkley on Oct 25, 2021 0:02:18 GMT -5
And if so, does God hold the patent? Is God a dirty capitalist? I'm sorry, Dirty Capitalist?
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Post by Roquefort Raider on Oct 30, 2021 8:23:36 GMT -5
Technically speaking E. coli went to the moon, but no Canadian ever did. That's a humbling thought!
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