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Václav Hrdonka
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Václav Hrdonka

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To je výbornej nápad ty střihy synchronizovaný s praskáním.
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Václav Hrdonka

Obecná diskuse o rodokmenech  - 
 
Tak to vidíte: Královská rodina má takový krásný rodokmen a stejně se nakonec ukáže, že všechno je jinak :-)
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At last, King Richard III of England has been reburied in Leicester Cathedral this week. And at the same time, researchers have announced even more evidence of infidelity that could potentially shake up his royal family tree. 
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..tak též je známá záměna našich dějin...*
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Václav Hrdonka

General Discussion  - 
 
The tree is really great. But whet about the conclusion? They stated that "the rate of diversification in eukaryotes has been mostly constant". How thy found it? They "have synthesized a global timetree of life from 2,274 studies". Well that is huge, but what about those studies? Does not they usually assume that the rate of diversification is constant? In such case it seems to be a logical loop. I miss some statistical analysis about the source of data to make such conclusion...

http://mbe.oxfordjournals.org/content/early/2015/02/20/molbev.msv037.full.pdf+html
Researchers have assembled the largest and most accurate tree of life calibrated to time, and surprisingly, it reveals that life has been expanding at a constant rate. The study also challenges the conventional view of adaptation being the principal force driving species diversification, but rather, underscores the importance of random genetic events and geographic isolation in speciation, taking about 2 million years on average for a new species...
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what is assumed (although it also has been tested) is that the random changes in non-selected DNA segments occur at a fairly constant rate. This is because the enzymes involved in DNA copying and repair have a(n extremely small) error rate. This rate has been investigated among and across taxa, and seems for the most part to be very, very consistent. This is actually unsurprising given that those basic enzymatic pathways have been evolved 2-4 billion years ago and are so critically impprtant that selection strongly works against significant changes in them.

As to the article/study, the online article doesn't say much conclusive about what was done specifically, but they do mention the average speciation rate, which indeed seems to be about 2 millions years, regardless of which taxon we're talking about (and this observation is entirely independent from the molecular findings I mentioned above).
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Václav Hrdonka

Article Highlights  - 
 
Souht America monkeys are really from Africa: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14120.html
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Václav Hrdonka

Dotazy k tvorbě rodokmenu  - 
 
Mám nalezeno už přes 850 přímých předků, hledám způsob jak tento rozsáhlý strom zobrazit, ideální by byl kruhový diagram. Nevíte někdo o nějakém rozumném softwéru, který to umí? (Mám to ve formátu GED)
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Já si grafické zobrazení rodokmenu kreslím ručně v LibreOffice Draw a následně si to exportuju ve formátu PDF. Mám to přesně jak chci, je to vektorový a můžu si to uspořádat tak, abych si to nechal vytisknout třeba na formát A1. Ve výsledku to vypadá takto http://www.jakubcabal.g6.cz/wp-content/uploads/2015/01/Rodokmen-rod-Cabal.pdf
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Václav Hrdonka

Hledám ztracené předky  - 
 
Můj pradědeček se narodil v Ahlsdorfu nedaleko Lipska v Sasku někdy kolem 1880-1890 nevíte někdo, kde by se nešly přesnější informace?
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Děkuju
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Václav Hrdonka

Obecná diskuse o rodokmenech  - 
 
Žádný vyfocený člověk se prý nenarodil dříve než tahle paní. Jaký je rok narození Vaší nejdříve narozené vyfotografované osoby v rodokmenu? 
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Prabába *5.2.1862 a 2x Praděda *25.11.1842 obě fotky z přelomu 19. a 20. století.
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Václav Hrdonka

Article Highlights  - 
 
You can read everywhere about Yawunik - the ancestor af all spiders, lobsters and insects. But that is not true. Yawunik falls into the group of the early chelicerata. If its an ancestor, its the ancestor of the spiders. Yawunik only has some features of early arthropods, it does not mean that it is the ancestor of all arthropods.
A multinational group of paleontologists has described a prehistoric lobster-like animal from the Marble Canyon site, part of the Canadian Burgess Shale.
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Václav Hrdonka

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Great finding!
Cranium discovery shows that Homo sapiens was living in Middle East 55,000 years ago.
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Awesome find!
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Václav Hrdonka

General Discussion  - 
 
New finding of Chancelloriid. Was it Lophotrochozoa related to Halkieriid? 
A rare 520-million-year-old fossil shaped like a 'squashed bird's nest' that will help to shed new light on life within Earth's ancient seas has been discovered in China by an international research team. The fossil is of a probable ‘chancelloriid’, a group of bizarre, balloon-shaped animals with an outer skeleton of defensive spines.
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Have him in circles
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