Hi Nick, welcome to the Forum! Thanks for your question.
There seems to be some confusion in your writing about the term lineage and about the mechanisms of evolution. I will try to clarify things a bit more.
A lineage describes a path of direct descent through any family. For example, there is a “backward” tree consisting of you, your father and mother, their parents, their parents’ parents, et cetera. Your own descendants would be a “forward” tree. Any line through this tree is a “lineage”.
The current picture is that the population from which humanity evolved consisted of about 10,000 people / hominids. If we descended from a population of about 10,000, it means that you can always find multiple separate lineages through the family tree. However, this does not mean that the evolution from primate to human occurred multiple times separately (i.e., in separate populations). I will now list a few important points that are useful to keep in mind when thinking about evolution:
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Evolutionary mechanisms such as natural selection operate on the population level, not on individuals.
Of course, changes in individuals can eventually spread to the whole population. But such spreading occurs through mechanisms which act on the entire population. Also, the reproductive unit of humanity is man and woman. So you cannot separate men from women on the population level (the level of analysis for evolution). The differences between men and women are coupled to each other, i.e., they only function together. -
Evolution occurs in any population with selective pressure.
The pressure results in a push to find local solutions. There are moments when populations change very rapidly due to evolution, but evolutionary mechanisms are acting on populations all the time. So it’s better not to speak of evolution “occurring” on specific moments, but rather of changes occurring in populations. -
Because evolutionary mechanisms act on the population level, they can exploit rare occurrences and complex contingencies.
Such contingencies are intimately dependent on the circumstances of the population and the environment. So just the fact that something happened in evolutionary history does not say anything about the likelihood that this will happen again. Currently, it appears that humanity evolved from a single population and hence exploited some specific conditions at the time.
However when we see something occurring multiple times in separate populations, things become more interesting. That’s what we call convergent evolution. Pablo de Felipe wrote an interesting BioLogos article called “Evolution on Purpose: The Inevitability of Intelligent Life?”. I suppose that touches upon the original intention of your question. Here’s a quote from that article:
Once life starts moving on, according to Conway Morris, the forces of natural laws would push and constrain it to paths across a biological landscape that could reach, not unexpectedly, the development of an intelligent being that would occupy a mental niche (of course, that does not mean that these beings had to be necessarily Homo sapiens!). As Conway Morris’ ideas have developed in recent years, he prefers the view of evolution as a search engine that explores the opportunities of life and, rather than just emerging in a pre-existent mental world, discovers it after navigating a constrained “hyperspace” of biological possibilities. We could be the first to set foot on this new beach, but it does not mean that we are entirely unique. As he remarks, the intelligence of other runners in this race of discovery, like corvids, dolphins and great apes, “suggests that equivalent search engines are only a few million years behind ourselves.”
So while evolution can lead multiple times to similar solutions, this has not happened (yet?) for our own unique capacities. I hope this will help you to get a clearer picture of the concepts of evolutionary theory and the evolution of mankind.