Does a pattern constitute evidence, logic or both?

Before they unraveled the secrets of DNA, scientists used a variety of patterns to help them classify living things. These patterns included similarities in appearance and behavior, similar range, and relationships reconstructed from the fossil record.

People also focus on patterns in help them understand the social sciences. For example, the strong have been preying on the weak since time immemorial. Another pattern some have noticed is that the media like to release potentially embarrassing stories on a Friday or Saturday, when many people are too busy enjoying the weekend to pay attention to the news.

Suppose someone invokes such a pattern in claiming that a theory is credible, or plausible. For example, "Its bone structure, combined with the location where its fossils are most common, suggest that this bird is related to the ostrich."

From the political arena: "What a coincidence that this story - which is really pretty sensational - was buried in the middle of the paper on Saturday morning, huh? Having witnessed this type of thing more times than I can count, I smell a cover up."

Would you say that either or both statements are based on evidence, logic, a combination of the two or something else entirely?

Let's start with your general question:

Does a pattern constitute evidence, logic or both?

In order to avoid the begging the question fallacy, you should add "or neither" as well :)

A pattern could often be considered evidence, and the strength of the evidence depends on the details as well as what the pattern is being considered evidence for. To use your examples,

1) A "pattern" of physical characteristics to classify organisms sounds a bit like we are shoehorning the word "pattern" in here. It doesn't quite fit the definition. We are referring more to common characteristics.

2) The media releasing stories on weekends they want to "cover up." Be careful not to overreach here. By this, I mean if what you perceive as an "embarrassing story" is run on the weekend, all we can conclude at this point is that what you perceive as an "embarrassing story" is run on the weekend, not that a "cover up" has occurred. Not yet. But here is where the patterns come in...

First, we need to make sure we have a reliable metric for what we consider an "embarrassing story." Then, we need to avoid the confirmation bias and make sure we have a good understanding of how often these embarrassing stories are run during the week versus on weekends. It might be the case that "embarrassing stories" are more for weekends (puff pieces) due to more important news during the week. In other words, a pattern such as this would be evidence for good publishing practice rather than anything nefarious. No doubt there are media sources with political bias, so for example, if MSNBC consistently (pattern) runs dirt about Trump during the week and Fox News holds those stories for the weekend, we can reasonably conclude (evidence) that we are witnessing bias (not really a "cover up"), but we cannot be sure whose bias at this point (likely a bit of both parties). Perhaps if one did have a media source that they felt was neutral, this can be a 3rd data point to see where the bias is.

As for logic, in the informal sense, extracting evidence from patterns is a logical process, as is knowing the that we have a tendency to see patterns where there are none (some much more than others - this is usually referred to as a pattern-seeking bias or Apophenia ). In a sense, "patterns" occur all the time in randomness (e.g., if you roll a die a 1000 times, it is a statistical certainty that you will get a long string of the same numbers). The real power of logic and reason is knowing when inferring meaning or agency behind the pattern is justified.

Based on my knowledge of the media (I'm a retired communication professor), the news outlets do not delay stories to the weekend. Pretty much never. A reporter makes his/her reputation by getting a scoop, by reporting stories as fast as possible before other reporters can beat them to the punch. To a reporter or editor, to delay a story is the kiss of death.

Much more likely is that politicians and businesses like to release bad news at the start of the weekend, hoping that their mistakes will be reported less enthusiastically.

So, you are committing the fallacy of post hoc, ergo propter hoc. That is, you are using coincidence to deduce a cause and effect relationship that doesn't exist.