Octavus t1_jdsj58i wrote


Octavus t1_jbp1pre wrote

The Y chromosome is unable to perform recombination so most damage is unable to be repaired. This causes loss of genetic information overtime, if the genes were critical to life the animal would be unable to reproduce. So only genetic losses that are no/low negatively impactful can be passed on.


Octavus t1_j97d735 wrote


Octavus t1_j7m8l40 wrote

Please note that hepatitis is a disease of the liver and not a family of viruses. The different hepatitis viruses are not related to each other in general, the only thing they have in common is that they all infect the liver.


Octavus t1_j25ymfi wrote

They have not been completely isolated for 50,000 years, there has been several periods of limited contact.

The most significant is ~10,000 years ago was when Australia was finally culturally split from New Guinea, there is also linguistic evidence as 90% of Australian languages are within the same family and split only a few thousand years ago. However this is before the isopoint so not related.

What is important is genetic and trade evidence between India, South East Asia, and the northwest cost of Australia. This trade and gene flow occurred ~4,300 years and gave enough time for Australia and Tasmania to become completely mixed in the 1,000-3,000 years before the contact.

This is technically only evidence of India -> Australia but the evidence points towards continue contact and not a one off event. Continued contact points to the people returning from Australia to the homelands which allows for gene flow the other direction. It simply takes one person to make the trip and have descendants.

The dingo has only been in Australia for 4,000-10,000 years. If Australians have been isolated for 50,000 years where did this non-native animal come from?

Genome-wide data substantiate Holocene gene flow from India to Australia


Octavus t1_j24z5w5 wrote

Their ancestry would spread to Alaska present day Alaska on only a few hundred years. Paleo Eskimo, who lives from Russia through Alaska into Greenland. They acted as the bridge between the old and new worlds 4,500 and 1,500 years ago.

The world has been much more interconnected than what most would believe. It takes only one person after complete mixing to spread an entire continent of ancestry. Do not underestimate just how much mixing occurs in 1,000 years, that is enough time to completely mix all of Europe.


Octavus t1_j20c6b6 wrote

There isn't believed to be anyone left in the Americas or Tasmania who does not have any European ancestry from the last 500 years.

Going the other direction Paleo Eskimo bridged the gap for a while between the Americas and Asia. Their culture spanned from Russia through Alaska into Greenland.

There was a continuous but some gene flow between Australia and South East Asia. Any other isolated groups of humans have only been isolated for a few hundred years.


Octavus t1_j1wd7i8 wrote

Cheddar Man lived before the human isopoint, if he has one living descendant then every single person on the planet is also his descendant. At some point 7,300 to 5,300 years ago if someone had a living descendant, then all of humanity is their descendant.



Octavus t1_j1j7ik4 wrote

Wikipedia has a handy graph showing the effect of general and special relativity for orbiting satellites in circular orbits. This highlights what you and others are describing.



Octavus t1_izd243f wrote

There are also viroids which are even simpler than viruses. They are simply a circular strand of RNA, that is it. However they are still able to infect plants, use their cellular machinery to create more copies, and spread.


Octavus t1_is6fwvr wrote

The study was not about memory, it was studying distance estimation. The actual title is Distance estimation in the goldfish (Carassius auratus). The BBC just made up a totally different title.


Octavus t1_is6fl3a wrote

The paper is not studying goldfish memory and the BBC article's title is just wrong. The actual title is Distance estimation in the goldfish (Carassius auratus).

They were studying how goldfish estimate distance swam, which apparently is via visual references.


Octavus t1_ircq1cf wrote

It sounds more like you are code switching, it is completely normal behavior. Some people do it stronger than others but we all do it, even if just switching between family, friends, or coworkers.