Evolution is random, it doesn't happen by necessity, it just can proliferate by a development being advantageous, typically to the capacity to successfully pass on genetic material across generations (and beneficial traits can become maladaptive).

The real decider is the environment, and how a trait benefits the chance of being passed on to future generations. Generally, the assumption is that if a trait gives a positive advantage in the environment, it is more likely to proliferate through the species and if its detrimental its likely to become extinct.

Also, maladaption is an issue. A once beneficial trait, can become detrimental when the environment changes, and as evolution occurs over gulfs of time, it generally means that becomes detrimental.

For example, the human stress response. This is very well adapted to about 80% of the human time line. However increasingly with civilisation responding to a stress in a primal manner (the flight or fight response) is damaging. The problem of course is that the efficiency of the flight or fight response in primal environments, meant that alternative traits were probably extinguished before the first humans even existed - and because it won't actually reduce your chance of spreading genetic material, its going to remain.

Evolutionary benefit also isn't individual benefit. Bright plumage increases a birds chance of reproduction more than its chance of being eaten, will of course proliferate and it just ends up sharpening up how close to mating season the first bright colours arrive....

Evolution would, if we attribute it with sentience, give you cancer at the age of 40, if it meant increasing your chance to get a girl pregnant at 15.

Or maybe Adam Johnsons defence...

Arguably the biggest question would be around how life originates, rather than evolves. We can probably safely say that once life occurs, it evolves and provided its not wiped out in the earliest phases it will spread and evolve over the life of the planet provided its capable of sustaining some of those life forms.

But how life begins, presumably involving amino acids, to construct RNA and DNA and single cell lifeform's is the great unknown factor.

Yes, but it creates the knowledge, that my own view point is itself flawed, and contains an unreliable bias, and with time, whilst not remaining objective, I can approach the subject with increased critical capability.

Humans, are paradoxically, not very good at any one thing, as a species. This kind of means they don't use up a lot of neural capacity on 'super senses' (meaning there is more 'capacity' to learn).

This, opposable thumbs, and an abnormality in the larynx, are largely responsible for the adaptation of humans as a 'highly successful species'.

The abnormality of the larynx, whilst increasing the risk of choking, allows for 40,000 plus vocalisations, rather than between 10-40 seen in most mammals.

This capacity for language, plus a relatively unspecialised brain (with great learning capacity) is mostly what attribute intelligence to (Language allows the sharing of experience, and knowledge, which arguably is the single most significant thing separating humans from other mammals).

But in truth, we're not actually all that intelligent, we just have a capacity to share knowledge and information, which makes us look and feel more intelligent (i.e. we can define what is and isn't intelligent, which brings us back to an humanocentric view of existence).

I'd back Stephen Hawking against Tibbles any day on Mastermind though

Hawking is s*** at climbing trees though and you rarely get people posting pictures of Hawking to their friends on Facebook.

Balance.