Artwork in a limestone cave in Sulawesi previously thought to be only 10,000 years old has now been dated to nearly 40,000 years using uranium-thorium dating techniques . That makes it the world's oldest artwork found to date, predating cave art in Europe.
Not only will this prompt a renewed search for similar cave art in Asia, it provides yet more evidence - as if any more evidence was needed - that humans have been on Earth far longer than 6000 years. Via Nature:
Though the paint itself cannot be dated, uranium-thorium dating can estimate the age of the bumpy layers of calcium carbonate (known as ‘cave popcorn’) that formed on the surface of the paintings. As mineral layers are deposited, they draw in uranium. Because uranium decays into thorium at a known rate, the ratio of uranium to thorium isotopes in a sample indicates how old it is.
The researchers dated 12 stencils of human hands and two images of large animals. Because they sampled the top layer of calcium carbonate, the uranium dating technique gave them a minimum age for each sample.
They found that the oldest stencil was at least 39,900 years old — 2,000 years older than the minimum age of the oldest European hand stencil. An image of a babirusa, or ‘pig-deer’, resembling an aubergine with stick-like legs jutting from each end, was estimated to be 35,400 years old — around the same age as the earliest large animal pictures in European caves. 
YECs claim that the universe is 6000 years old. This artwork is nearly seven times older than this date. Needless to say, this falsifies YEC claims about Adam being the first human being to walk the planet. Completely. Claims that the dating methods are inaccurate are false. Radiometric dating is reliable when used correctly.  There are no credible arguments to be made against the great age of the Earth, a point that early Christadelphians were honest enough to acknowledge:
I have not the slightest doubt concerning the truths revealed in the strata of the earth’s crust. There can be no reasonable doubt that long ages have passed away since the matter of the earth first took existences by the fiat of its Almighty Creator. … The facts of old mother earth’s storehouse are too convincingly inscribed upon her crust to allow me to doubt.’, 
Ten years ago the average scientist would have asserted that our habitable globe had not existed for more than a hundred million years. Now it would be hard to find a competent physical specialist who would fix a definite maximum below a thousand million years.  .
Whether this discovery will be enough to convince the YECs in our community of the utter falsity of their views remains to be seen, but as evidence like this percolates through to the lay audience, it will be increasingly more difficult to defend a 6000 year old age for the human race to our community, let alone a scientifically literature audience to whom we want to preach the gospel.
1. Aubert, M. et al. "Pleistocene cave art from Sulawesi, Indonesia" Nature (2014) 514:223–227
2. Cyranoski D "World's oldest art found in Indonesian cave" Nature 8th October 2014
3. Wiens R Radiometric Dating: A Christian Perspective Wien's article is required reading for every YEC in order to disabuse them of their mistaken belief in a young universe.
4. Welch., 'Knowledge.- No., 12 Geology', The Christadelphian (1891) 28:416
5. Walker C.C., "The Age of the Earth", The Christadelphian (1911) 48:450