For ideological reasons Neo-Darwinism has to interpret evolution as directionless (directed evolution is incompatible with materialism). This, however, contradicts not only common sense but the facts too:
The very great complexity of life, and especially its quite fantastic holistic nature, which seems to preclude any sort of evolutionary transformations via a succession of small independent changes, is perfectly compatible with the notion of directed evolution. ( ibid., p.383-384)
Natural selection, acting upon random mutations, could never produce such results. Denton collected data on every level of biological organisation that renders directionless evolution unlikely. He concludes:
The evolutionary evidence is similar; it compounds. In isolation, the various pieces of evidence for direction, the speed of evolutionary change, the fantastic complexity of living things, the apparent gratuity of some of the ends achieved, are perhaps no more than suggestive, but taken together, the overall pattern points strongly to final causes... No other explanation makes as much sense of all the facts. ( ibid., p.384-385)
This, of course, does not mean that every biological blueprint is directed. Any particular form will depend on the available genetic material and environmental circumstances. There are many contingent adaptations (particularly noticeable in isolated environments). The evolutionary pull can be compared to the gravitational force that pulls river water in the same general direction. In conjunction with the environmental constrains a river-bed is created as a loose boundary that determines its general flow. Within this flow some variations can occur that may appear to have a different (even opposite) direction or stagnate. Similarly, many evolutionary lines are dead ends. Although there is a general trend towards complexity, some organisms get stuck in evolutionary terms, and sometimes even regress. Nevertheless, as with a river, an overall flow is maintained.
Broadly speaking, two dimensions (or directions) of biological evolution can be discerned: the horizontal (characterised by an increase in organisation, integration and diversity - expansion of life to unoccupied environmental niches) and the vertical (characterised by an increase in complexity, specialisation and dynamics). Both processes lead to a relative decrease in entropy. From this perspective, animals, for example, are a step further ahead than plants in the process of evolution:
Animals are highly ordered systems that in contrast to most plants are largely synthesized from highly ordered (low-entropy) molecules. (Silver, 1998, p.352)
Ultimately, however, the aim of biological evolution can be linked to producing forms that would enable development of the non-material energy. This primarily means increasing and refining its main properties - awareness and intent, that are exercised through life experiences in the material world. So, the purpose of biological evolution can be defined as an enhancement of awareness and intent through developing more complex and independent biological forms. In other words, species become more aware and gain more control through the processes of evolution, fulfilling an overall tendency of life towards self-actualisation.
To avoid chaos though, this increase needs to be carried out in manageable steps, which is achieved through internal and environmental constraints. Thus, evolution can be seen as a result of the interaction between the material and non-material components of life, within the pre-set but dynamic boundaries that expand throughout the process. So, evolution starts with narrow awareness and intent that gradually develop, while the strength of biological and environmental determinism decreases. Greater awareness means that more energy can be affected by the self. The self is at the beginning a relatively passive observer and does not have a big impact, but through the process of evolution the individual selves become more pro-active and their influence grows. In other words, the role of intent becomes more prominent. It is reflected in a reduction of predictable, predetermined actions and behaviour.
To summarise, evolution enables individualisation and also the shaping and refining of energy, which is compatible with the overall aim of life. If evolution is characterised by the increase of complexity and organisation, and if the One is the source of the most complex and organised phenomena, the end result must be to become an equivalent, counterpart to the One.
This process is enabled mainly by a growth in complexity of the nervous system (more can be done with an advanced computer than with a simple one). Indeed, the awareness of higher organisms seems broader and more complex. Generally speaking, animal species are more aware than plants, and humans are more aware than animals. The self of an animal is capable of focusing (holding together) a relatively small range of qualitatively different pieces of information. Some of them may hear or smell better than humans, but they are not aware of much more besides these sensations, because their ability to organise and structure what they are aware of is limited. Thus, the consciousness that humans possess did not appear accidentally, but as a stage in the evolutionary process. There is a sound empirical basis for this assertion.