...and you may claim that that is no plan .. but merely cause and effect yet it is causes and effect with an ultimate objective - sustainability ( a long term agenda). Thus it could be argued to be indeed "a plan".
I don't think that is a logical conclusion. What if we use the example of species that did not survive? Was there a grand plan at work for them? How about the Neanderthals?
As you correctly indicated "but merely cause and effect yet it is causes and effect " (i.e. constant change) from which an Implicate Order emerges. Some things die, some things live. No plan.
It's as simple as that, IMO...
If we were dealing with humans only I might tend to agree.
But we are not and no creature except humans will consciously choose to live in inhospitable environments and be forced to "strive" to survive. For all animals except humans and their pets survival in any kind of environment is hard enough. When it gets too hot, there is mass migration to cooler areas, when it gets too cool there is mass migration to warmer climates. And soon we may see a human migration away from coastal plains due to rising sea-levels. That is also part of striving to survive.
Only humans and a few insects can manipulate their environment to make inhospitable areas
survivable. Ants and Termites have practised agriculture for a hundred millions of years, long before humans appeared on the scene. In fact, some of the labor force of a termite hive never gets to see daylight. They are confined to underground gardens for their entire lifespan. Of course they do have plenty to eat...
Thus while it may seem there is a grand plan, there is no such things, but long term probabilistic events. If you play the lottery long enough you're bound to win something. That does not count as a prior existing greater plan. It's just luck spread out over trillions of natural tries over a span of millions or even billions of years.
All this may seem like a plan but in reality it is just a hierarchy of natural mathematical physical functions which behave in a pseudo-intelligent consistent manner.
ions.