The phrase "ancient samples" is correct and usable in written English.
It can be used when referring to samples that are very old, often in contexts related to archaeology, geology, or historical studies.
Example: "The researchers discovered ancient samples of pottery that date back thousands of years."
Alternatives: "historical specimens" or "old artifacts".
Link, V. et al. ATLAS: analysis tools for low-depth and ancient samples.
In addition to damage, ancient samples can acquire exogenous contamination that may obscure any remaining endogenous signal.
We successfully genetically identified the species of 27 ancient samples, of which 15 were bowhead whales (Supplementary Fig. S1).
Since then, researchers have adopted strict procedures to ensure they are not contaminating ancient samples with modern-day DNA.
(a) Map showing the sample location of the brown bears analysed using mtDNA, including information on what clades they belong to; ancient samples (dots), modern samples (triangles).
However, the number of analysed ancient samples from the Mediterranean area, where U7b has elevated frequencies today, is still rather small.
(B) Distribution of mtDNA K1 (circles) and Y chromosome G2a (rectangles) haplogroups in ancient samples dated > 5,000 ybp and their absolute frequencies.
The ability to recover ancient samples of DNA provides an opportunity to study long-term evolutionary changes that may affect the epidemiology of microbial pathogens.
Isolation and quantification of this component is therefore of great interest in radiocarbon measurement, particularly for more ancient samples, where contamination issues become more critical.
Human DNA quantification has become an essential means to evaluate the preservation of ancient samples and to ensure the authentication of the results in ancient DNA research.
But collecting ancient samples was just the first step.
