It's just about that time again. In a couple of weeks, I'll be off to the temporary fossil capital of the world, the Tucson Gem and Mineral AND Fossil show. I'll be blogging this year. Stay tuned.
Welcome to the Miller's Fossils Blog
Monday, January 9, 2012
Boogie Back to Tucson
It's just about that time again. In a couple of weeks, I'll be off to the temporary fossil capital of the world, the Tucson Gem and Mineral AND Fossil show. I'll be blogging this year. Stay tuned.
Thursday, December 22, 2011
More on Evolution
I must confess that the last three or four weeks have been one of the most transformational times in my life. I've spent the last twenty years of my life trying to learn as much as I could about fossils and Paleontology to a somewhat lesser degree - pretty much bypassing evolution as such because it seemed rather cut and dried. Individual animals and populations of animals adapt/change either physically, physiologically, behaviorally thru their interaction with natural selection and their dna changed at some basal level.
I finally got around to reading "Your Inner Fish" by Neil Shubin about a month ago and was wowed for the 1st part, kinda understood the the middle ( the universality of the tetrapod body plan) but my eyes glazed over in the last part (HOX genes, etc.). But after watching a show called "What Darwin Never New" tonight, I realize that the third part of Shubin's book was the most important.
Only about 2% of our genes actually lead to the building of proteins which "we" always new is what genes did. But 98% of our DNA has been called "dark matter" because it didn't seem to do anything. We now know that some of that dark matter (regulator dna) actually turns that 2% off and on and that very small off/on differences lead to very different expressions even though the 2% remains unchanged. Additionally, another part of the dark matter (ie HOX genes) control the regulator genes (how long off/on, how much is produced per time period).
The show gave an example of two species of fruit fly. One sported wing spots and one didn't but they were able to determine that both species had the same genes that coded for wing spots. Thus the expression of the gene or lack thereof seemed to be the reason that drove one species into two - not a change in the basic protein producing gene.
I am absolutely absorbed by this new understanding of the basis/basics and mechanisms and their implications of evolution.
Different but related portion - Bite force seems to be a basic cause of differences between humans and apes. Apes have a very strong bite force that is the result of the muscles that pass within their zygomatic arches one result is that that forces the plates of the skull to fuse in about 3 years from birth. Fused skull means the end of brain growth. In humans, skull plates don't fuse until about 30 years of age. Unfused skull plates allow brain size to increase for decades.
I am overwhelmed by this stuff - join this topic if you wish. Try to get the book and see the show.Monday, October 31, 2011
Great Moments in Evolution and Adaptation
Even lowly parasitic protozoa are subject to the same rules of nature as the rest of us inhabitants of the living world. According to Wikipedia, Toxoplasma gondii:
The life cycle of T. gondii has two phases. The sexual part of the life cycle (coccidia like) takes place only in cats, both domestic and wild (family Felidae), which makes cats the parasite's primary host. The second phase, the asexual part of the life cycle, can take place in other warm-blooded animals, including cats, mice, humans, and birds. The hosts in which asexual reproduction takes place is called the intermediate host. Rodents are the typical intermediate host.
Recent studies indicate that to enhance the ability to move to the critical cat stage T. gondii produces changes in rat brains so that infected male rats do not fear the scent of cat urine. How does that work? When infected male rats smell cat urine, the area of the rat brain that responds to FEMALE rats becomes activated. As such, the protozoa causes male rats to seek out their predator and thereby allow T. gondii to reproduce!
The life cycle of T. gondii has two phases. The sexual part of the life cycle (coccidia like) takes place only in cats, both domestic and wild (family Felidae), which makes cats the parasite's primary host. The second phase, the asexual part of the life cycle, can take place in other warm-blooded animals, including cats, mice, humans, and birds. The hosts in which asexual reproduction takes place is called the intermediate host. Rodents are the typical intermediate host.
Recent studies indicate that to enhance the ability to move to the critical cat stage T. gondii produces changes in rat brains so that infected male rats do not fear the scent of cat urine. How does that work? When infected male rats smell cat urine, the area of the rat brain that responds to FEMALE rats becomes activated. As such, the protozoa causes male rats to seek out their predator and thereby allow T. gondii to reproduce!
Tuesday, October 11, 2011
Release the Kraken!
Well, the Kraken has been all the rage in Paleontological news recently courtesy of one Professor Mark McMenamin of Mount Holyoke College. I've never been to the Berlin-Ichthyosaur Museum in Nevada, but I bet it is interesting. The fossils of perhaps 37 40foot long ichthyosaurs lined in a row have been found there. Basically Prof McMenamin has proposed that some giant sea monster caused their demise and then artfully positioned them in its own image for us to see. That's SOME Kraken!
Apparently the good doctor has not been shaving with Occams Razor (not quite "the simplest explanation is usually the correct one," but close). The previous expanation has been that it was a stranding. Well, the new interpretation is certainly an interesting CSI investigation, but don't hold your breath.
I'm not sure why the media has picked this up and run with it, but as media critics say, "If it bleeds, it leads." It certainly has put this museum back in the news.
Apparently the good doctor has not been shaving with Occams Razor (not quite "the simplest explanation is usually the correct one," but close). The previous expanation has been that it was a stranding. Well, the new interpretation is certainly an interesting CSI investigation, but don't hold your breath.
I'm not sure why the media has picked this up and run with it, but as media critics say, "If it bleeds, it leads." It certainly has put this museum back in the news.
Wednesday, October 5, 2011
Saturday, September 3, 2011
If You Have Ever Wondered #2
More "if you've ever wondered..." This one is about the extinct Tasmanian Tiger and comes from Science Daily.
"They knew from previous research that the elbow joint was a clue to predator habits, as it showed whether the animal was built for flexibility and dexterity in handling prey or for chase and speed in tracking down the next meal. Examining the bones, they found that the thylacine's humerus, or upper arm bone, was oval and elongated at the end closest to the elbow, implying that the animal's forearm bones, the radius and ulna, were separate. That means the Tasmanian tiger would have been able to rotate its arm so that the palm faced upwards, like a cat. The distal humerus on dog-like animals, such as dingoes and wolves, is "more squared-up and shorter," Janis said. This indicates the radius and ulna were closer together in these species, reflecting that these animals' hands are more fixed in the palm-down position.
In terms of hunting, the increased arm and hand movement would have given the thylacine a greater capability of subduing its quarry after a surprise attack. Since dingoes and other dog-like creatures have less latitude in arm-hand movement, that helps explain why these animals hunt by pursuit and in packs, rather than in an ambush setting, the researchers note.
"It's a very subtle thing," said Janis. "You never would think that the shape of just one bone would mean so much."
Yet some cats, like cheetahs, use speed to catch their quarry, while some canid species, like foxes, rely more on the guile of the ambush. Janis said the thylacine's hunting tactics appear to be a unique mix. "I don't think there's anything like it around today," she said. "It's sort of like a cat-like fox."
"They knew from previous research that the elbow joint was a clue to predator habits, as it showed whether the animal was built for flexibility and dexterity in handling prey or for chase and speed in tracking down the next meal. Examining the bones, they found that the thylacine's humerus, or upper arm bone, was oval and elongated at the end closest to the elbow, implying that the animal's forearm bones, the radius and ulna, were separate. That means the Tasmanian tiger would have been able to rotate its arm so that the palm faced upwards, like a cat. The distal humerus on dog-like animals, such as dingoes and wolves, is "more squared-up and shorter," Janis said. This indicates the radius and ulna were closer together in these species, reflecting that these animals' hands are more fixed in the palm-down position.
In terms of hunting, the increased arm and hand movement would have given the thylacine a greater capability of subduing its quarry after a surprise attack. Since dingoes and other dog-like creatures have less latitude in arm-hand movement, that helps explain why these animals hunt by pursuit and in packs, rather than in an ambush setting, the researchers note.
"It's a very subtle thing," said Janis. "You never would think that the shape of just one bone would mean so much."
Yet some cats, like cheetahs, use speed to catch their quarry, while some canid species, like foxes, rely more on the guile of the ambush. Janis said the thylacine's hunting tactics appear to be a unique mix. "I don't think there's anything like it around today," she said. "It's sort of like a cat-like fox."
Friday, July 15, 2011
Monday, June 13, 2011
New Fossils for Sale
Check back to Miller's Fossils for some new fossils for sale this week. I'm adding videos of many items.
Monday, May 16, 2011
Wednesday, May 11, 2011
If You Have Ever Wondered
If you have ever wondered what paleontologists really do, check this out:
What does a pleontologist really do?
What does a pleontologist really do?
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