Pity the poor young-Earth creationists. When Darwin and Wallace produced their papers, the evidence for their position was confined to part of biology and a fraction of the nascent science of geology. The situation is quite different today.
All of astronomy and astrophysics report the huge size of the universe. With a finite speed of light, and theoretical physics now centers around the constant speed of light, that requires billions of years for the light from distant galaxies to reach us. Creationists have postulated a slowing of the speed of light over time, but that would simply leave the light rays too attenuated to be seen.
The age of some rocks is measured by minerals. Technically this is part of geochemistry, but the argument is simple enough for anyone who has taken freshman Physics or Chemistry -- maybe high-school Physics or Chemistry -- to understand. Radioactive isotopes of some elements formed compounds with other elements, and these compounds went into minerals found in the rocks. The isotopes decayed into different elements -- ones which would not form compounds with the elements the original isotopes did. The ratio of decay elements to the original isotopes measures the age of the minerals, and thus -- usually -- the age of the rocks.
Close study of glaciers reveal a pattern of layers like tree rings. The layers run several to the inch, and Antarctic glaciers are miles deep. So the glaciers reveal information about many times the years that young-Earth creationists say that the Earth has existed.
The expansion of evidence in biology and geology after the jump.
The sheer quantity of fossil finds, of course, has multiplied since Darwin and Wallace. Volume is, however, not a very convincing argument. If you aren't persuaded by ten fossils; you're unlikely to be persuaded by ten thousand. When you understand that the "White Cliffs of Dover" are compressed ancient sea shells, however, it is difficult to argue that they were laid down in a few thousand years.
In general, the layers of sediment that geologists speak of as being laid down over millions of years -- and the deep erosions that can be seen -- are regarded by Y-E Creationists as the result of one, or a few, floods. Well, North India, between the Himalayas and the Deccan, is sediment which flowed from the Himalayas as they rose. Rain erodes rock slowly, and sea water flowing over it erodes it much more slowly.
Then, too, some of the oldest individual plants -- not the oldest species -- are trees growing in the Grand Canyon. They have rings, and those rings go back to before the date Y-E Creationists give for the creation, let alone the flood.
Many species of mammal have valves in the arteries of their legs which prevent blood from pooling in their feet. The arteries in the trunk do not have those valves, and they don't need them because the arteries do not run vertically -- except in a few species. Humanity is one of those few species. So, you have those valves in the arteries of your arms, which are only sometimes vertical. You don't have them in the arteries of your main body, which is usually vertical. As you do have them in your legs, the blood often pools before entering your legs; we call those hemorrhoids. It is hard to see valves where we don't need them rather where we do as Intelligent Design.
Then, too, the entire series of results of DNA sequencing demonstrate relationships across the Linnaen family tree. Cows are genetically closer to whales than to horses.