Writing is often all about research. Yeah, I’m a little biased because I write so much nonfiction but even in fiction you sometimes find yourself doing research.
One of the things that I emphasize with my students is finding recent source materials. No matter what you are writing about, you need to find sources that are less than 4 years old. Yes, even if you are writing about history or archaeology.
Recently, I decided to take a couple of online university level courses. I want to write more science and I was hoping that my degree in anthropology would help me understand some biology topics if I started with the right ones. First I took Evolution: A Course for Educators through The American Museum of Natural History. I knew that some of my confusion was simply a matter of disciplines. Theirs is biology and mine is anthropology so we discuss things a little differently. But some times things just didn’t line up so now I’m taking Human Evolution through the University of Wisconsin – Madison.
With this topic, which is more narrowly defined, I have a much better understanding about where my confusion originated. The reality is that things have changed.
No, early pre-humans haven’t changed. They are still whoever, or whatever, they were so very many years ago.
What has chanced is what we know about them. New fossils have been discovered. They aren’t all new fossils of known beings. These were completely and utterly unknown when I was in college. How we study these fossils has also changed because genetics has come a very long way. Not only are there new names to learn, some of the old ones have changed or been moved in how they relate to one another.
Even if you are writing about something that is long gone, you need to find the recent materials. No, your topic hasn’t changed but our understanding of it may have changed a great deal. All it takes is one new discovery or a new way to examine things.
–SueBE
One Writer's Journey 
Can’t agree with you on this one. I have a master’s degree in history with a focus on the Ancient Mediterranean and Modern Europe. Both specialties routinely use texts much older than 4 years. More important is the thoroughness and impact of the historian’s work, not that they are recent. In history, as with many disciplines, certain focuses or trends come in and out of popularity. Any historian worth her salt should definitely read the accepted masters – such as Gibbon (Decline and Fall of the Roman Empire) in addition to more recent takes. Yes, even kids. Having written for kids for some years now I can support that statement.
I suspect that what you’re saying applies much more strongly to science, but even in science there are some texts that stand out and above others for usefulness. These are usually revised multiple times to incorporate the latest info, of course.
Sorry, I too have a Master’s Degree in history and I worked in archaeology (as in prehistory), and I’m standing firm. Yes, I read many texts that were older than four years for my thesis, but I also conducted hours and hours of oral history interviews. This was all new data, much less than four years old. Without it, my work would have simply reiterated what other people had already found.
You need to know the classics since they are what all of the rest refers to, but you also need to know about recent finds and newly discovered materials. If you don’t, then you are relying on incomplete information. No, it may not change much but it can change. And if you don’t stay current, you have no way of knowing.
–SueBE
Current is relative in ancient history, which is where I’ve done a lot of my work. There’s not a lot of earthshaking developments on a regular basis, but there is a lot of reinterpretation of text and evidence and so forth. I get what you’re saying and I’m not entirely disagreeing – just saying that while current is important, in some specialties it’s more crucial than others.
I’ll never forget the moments I realized birds are related to dinosaurs, Pluto’s not a planet, and there’s an additional ocean, the Southern Ocean. Science changes each and every day. And, as you note, it behooves us to make sure we have the most current research.