Originally thought to be 40,000-year-old Neandertals, the fossils were later reclassified as Homo sapiens—and eventually redated to roughly 160,000 years ago.

As the old saying goes, dogs are man’s best friend.

Dogs perform many useful tasks—from hunting to security to helping people with disabilities.

The analysis adds new twists to prevailing notions about archaic human history.

"Denisova is a big surprise," says John Hawks, a biological anthropologist at the University of Wisconsin–Madison who was not involved in the new research.

And this isn’t really an assumption as the decay rates have been tested in the laboratory for a hundred years or so, we have an example of a natural nuclear reactor where we can measure the various products and determine the decay rates (and the fine structure constant), and we can observe the past by looking deep into the past of the universe. The sigh isn’t for the effort of writing, it’s for the effort of finding all the references.

The other is that the decay products of various atoms are always the same. Just looking at this list, I can see that none of these are actually assumptions used by radioactive dating methods and/or they are known issues and compensated for. Something that this particular website has none of. Basically, just like all creationists, they are making stuff up and then hoping you won’t check them on it. 1) atmosphere has always had the same amount of C-14 This is obviously in reference to carbon-14 dating of formerly living tissue.

Most of us would agree that we’re just glad they’re part of the family! How can we explain the tremendous variety of dog breeds?

The first is that atoms have always decayed at the same rate.

What is especially interesting is that the fossils do appear to show a progression from the most "simple" of organisms, such as single celled creatures like bacteria, to the most "complex" organisms, such as vertebrates, mammals, and of course humans.