It has been long to be sad By Prof Dr Sohail Ansari & DNA And Learning
Waiting is
painful. Forgetting is painful. But not knowing which to do is the worse kind
of suffering. Paulo Coelho“Be not wishing and
pining but thankfully content. For it is a short bridge between wanting
and regret." from "Dimpellumpzki
Excess even of joy is bad
Excess even of joy is bad
·
Excess of anything is bad; you may soon be pining for the joy of
being sad.
The purpose of life
Interestingly,
the purpose of life according to the Quran was the topic of a lecture
delivered by Jeffery Lang, American professor and author who was an atheist before
accepting Islam
Lang realized that those verses show
Adam- and mankind- as learning creatures. The verses show that Adam is being
taught by God, and in life all sons of Adam will continue to learn through all
life experiences. Through language and communication, man can learn, not only
through personal experiences, but through the experiences of others of
different times and locations.
Lang noticed that “time
and time again the Quran calls upon man to use his intellectual faculties, and
swear by his intellectual faculties and to use them correctly, because they
play a fundamental role in guiding him to truth” (Lang).
Lang found that the Quran
repeatedly asks the readers to think and reflect. He observed that the word ‘ilm’-
which means knowledge-, is mentioned around 854 times. In many locations, the
Quran asks the readers “‘have you considered this or that” “Did they not
ponder.”
He also found that the Quran
stated over 100 times that it was revealed to make things clear, and over 21
times that in the Quran there are signs and lessons for those who are wise and
use their reason.
He realized, accordingly, that “to
gain truth or faith we need to free ourselves from inherited notions and
examine our beliefs rationally. Learning plays a key role in human development.
‘Read!’ the Quran exhorts the reader. God taught us the use of the pen and
taught human kind what it otherwise could not know. In life, nature and history
there are signs and lessons for those who are wise. God teaches humanity both
directly and indirectly and sometimes so subtly that we are unaware of his
instruction. Thus, He touches us in multifarious ways.” (Lang)
DNA &
Forms of learning
Early humans did not
understand the mechanisms of inheritance, of DNA, or of the translation of
genetic information into morphology, physiology, or behavior. But they
intuitively understood that inheritance shapes
behavior. By controlling mating,
herds and flocks of animals useful to humans were domesticated. The resulting
domesticated animals — cattle, horses, and dogs — behave very differently than
their wild progenitors. Selective breeding was a
key insight in human history,
even if the underlying science was not understood until the Darwinian and
Mendelian revolutions in the nineteenth century.
Today, we easily recognize that both genes and the environment influence behavior, and scientists studying behavior focus on the interaction between these two factors. Genes, via their influences on morphology and physiology, create a framework within which the environment acts to shape the behavior of an individual animal. The environment can affect morphological and physiological development; in turn behavior develops as a result of that animal’s shape and internal workings. Genes also create the scaffold for learning, memory, and cognition, remarkable mechanisms that allow animals to acquire and store information about their environment for use in shaping their behavior.
Today, we easily recognize that both genes and the environment influence behavior, and scientists studying behavior focus on the interaction between these two factors. Genes, via their influences on morphology and physiology, create a framework within which the environment acts to shape the behavior of an individual animal. The environment can affect morphological and physiological development; in turn behavior develops as a result of that animal’s shape and internal workings. Genes also create the scaffold for learning, memory, and cognition, remarkable mechanisms that allow animals to acquire and store information about their environment for use in shaping their behavior.
Instinct and Behavior
Instinctive, or
hard-wired (i.e., by definition, genetically determined), behavior captured the
interest of Charles Darwin, and later, of the ethologists such as Niko
Tinbergen. Instinct implies that
a behavior is performed without thought and cannot be modified by learning. Examples of instinctive behavior include
simple behavioral patterns, displayed in response to a specific stimulus or
within a specific context. A
cockroach flees to the protection of a dark nook when a light is switched on. A
dog may circle on its bedding several times, as if it were trampling
vegetation, before settling to sleep. A rattlesnake will strike at a moving, mouse sized, warm
object. In none of these cases does the animal engage in learning or thought when shaping its response.
Genetic (innate)
information best determines behavior when a species’ environment varies little from generation to
generation, or in communication when unambiguous messages need to be sent and
received.
Similarly, many of the
signals used in animal communication are innate, produced the same way by all
members of a species. The constancy that comes from having the signal and its interpretation genetically encoded makes the
message unambiguous.
Combinations of facial
expressions, hair erection, and tail posture give dogs (to other dogs) a
universal set of messages. Other animals use combinations of genetic and
learned information in forming their signals. Some birds can produce elements
of their songs without ever having heard another bird sing, but require hearing
songs during development to reproduce the song of their own species correctly. This last example demonstrates how innate
components can be used as building blocks for modifiable behavior, but animal behavior can be innate, reflecting a
strong genetic basis.
Imprinting and Development
Imprinting involves
the ability to learn a specific essential piece of information at the right
stage of development. Openness for learning through imprinting is restricted to
a short time span, called a critical period. The most famous example of imprinting comes from Konrad Lorenz
and his geese. He found that
goslings learn to recognize their mother (and to tell her from other geese)
very early in life. By substituting himself for the mother goose at the right
developmental stage, he could get the
goslings to imprint on him,
and faithfully follow him wherever he went. The openness of goslings for
learning a leader, even if it does not resemble a goose, is intriguing.
Imprinting demonstrates how genes can largely shape a behavior, but that evolution can create a window for learning
important information about variation
in the environment.
Imprinting provides an
opportunity to learn key variable
components in an environment while
retaining largely innate behavioral patterns. More flexibility
may be shown in the development of food preferences, as food availability can
vary from habitat to habitat, or from season to season. Insects may imprint on
the chemistry of the leaves they eat as caterpillars; when they become adults
they then choose to lay their eggs on plants with a chemistry that matches the
leaves they ate when young. This insures a suitable diet for the next
generation. Young birds and mammals often learn food preferences based on food
shared by adults, on observations of feeding preferences of adults, and on
sampling possible food items.
Another form of learning involves aversions, which can develop at any point in any animal’s life. Birds and mammals develop lifelong aversions to specific foods that contain poisons that cause sickness (such as monarch butterflies). In contrast, some preferences and aversions appear to be innate, or at least to be driven by physiological needs for certain nutrients, such as salt.
Another form of learning involves aversions, which can develop at any point in any animal’s life. Birds and mammals develop lifelong aversions to specific foods that contain poisons that cause sickness (such as monarch butterflies). In contrast, some preferences and aversions appear to be innate, or at least to be driven by physiological needs for certain nutrients, such as salt.
Learning About Specific Environments
Many animals learn key
information for survival. These abilities are often very specific to a
particular context. A species may be very adept at learning facts that are
relevant to its survival, but
not be able to employ learning across a broad range of situations that did not
occur in its evolutionary history. For example, native birds in Guam were completely unequipped to learn how
to evade predation by brown tree snakes, which were introduced into Guam about
1950.
Another good example of this comes from animals that store (or cache) food. Caching is an adaptation to cope with food supplies that are abundant during a short season, such as fruits and the nuts from trees. Some animals cache their food at a central location. Honeybees storing honey exemplify this, and centralized caches can require strong defense against thieves, a notable ability of honeybees. Alternatively, cached food can be scattered through the habitat; tree squirrels and gray jays are notable for scatter caching (this is sometimes called scatter hoarding) (Steele et al. 2008). Scatter caching of food stands out as a particularly challenging context for learning complex information about locations, and birds and mammals that cache food often display impressive abilities to recall cache locations.
Another set of examples comes from animals that leave their nests to forage, and must therefore learn enough about their environment to find their way home. The location of a nest or burrow is highly unlikely to remain constant across many generations; the ability to return home requires the ability to incorporate much environmental information. Some animals, such as the desert ant, Cataglyphis cursor, incorporate learning into navigation by using path integration, which is the ability to remember the distances and directions traveled, to sum them, and then to calculate their return path (Müller & Wehner 1988). Well-developed learning and calculation abilities are required to integrate a navigational path. Other animals use landmarks, like the position of the sun, to learn their outward path, which they then use in reverse to return home. Evolution has provided the innate tools for incorporating learned environmental information in cache retrieval and homing.
Another good example of this comes from animals that store (or cache) food. Caching is an adaptation to cope with food supplies that are abundant during a short season, such as fruits and the nuts from trees. Some animals cache their food at a central location. Honeybees storing honey exemplify this, and centralized caches can require strong defense against thieves, a notable ability of honeybees. Alternatively, cached food can be scattered through the habitat; tree squirrels and gray jays are notable for scatter caching (this is sometimes called scatter hoarding) (Steele et al. 2008). Scatter caching of food stands out as a particularly challenging context for learning complex information about locations, and birds and mammals that cache food often display impressive abilities to recall cache locations.
Another set of examples comes from animals that leave their nests to forage, and must therefore learn enough about their environment to find their way home. The location of a nest or burrow is highly unlikely to remain constant across many generations; the ability to return home requires the ability to incorporate much environmental information. Some animals, such as the desert ant, Cataglyphis cursor, incorporate learning into navigation by using path integration, which is the ability to remember the distances and directions traveled, to sum them, and then to calculate their return path (Müller & Wehner 1988). Well-developed learning and calculation abilities are required to integrate a navigational path. Other animals use landmarks, like the position of the sun, to learn their outward path, which they then use in reverse to return home. Evolution has provided the innate tools for incorporating learned environmental information in cache retrieval and homing.
Environment, Genetics and Cognitive Development
Cognition allows
animals to separate themselves
from the immediacy of their environment and to
reflect on the past in order to solve future problems. Cognition involves the ability to make novel
associations. Cognition was once thought to define humanity, or to separate humans from animals, but scientists now recognize that cognitive
abilities are not confined solely to humans. Learning through cognition may be
more removed from genetic
constraints than other forms of
learning, but cognitive problem solving ability can vary substantially among
different animals within a species. Variation in ability is inherited, so at
its core, there is a genetic element underlying cognitive abilities. Cognition
gives animals a high level of flexibility in their social and physical
environments, but even cognition is ultimately constrained by genetic limits.
One interesting aspect of cognition is that it can allow an animal to distinguish itself as a distinct identity. If an animal looks at its own image in a mirror and recognizes "self" rather than identifying the image as another animal, then some investigators interpret this as evidence of cognition. A common test is to modify the visual appearance of an animal (e.g., dying a patch of hair) and then observe the reaction of the animal to its mirror image. If it touches the dyed patch this is taken as evidence for the animal having a concept of "self." Apes, some monkey species, elephants and dolphins, all respond positively in mirror tests, supporting the idea that cognition is important in behavioral development across a broad range of animals (Plotnik et al. 2006).
Social cognition, the ability of an animal to forecast how its own actions will affect its future relationships within a social group, exists in chimpanzees (although it is more limited than in humans) and may extend to other species. In social groups without cognition, behavioral interactions are very much "in the moment," driven by factors such as dominance and family membership. Social cognition allows animals to be more calculating and manipulative in their social relationships. Chimpanzees do not appear to be mean to other members of their social group without justification, but they can, and do, exact revenge against group members that exhibit selfish behavior (Call 2001, Jensen et al. 2006).
One interesting aspect of cognition is that it can allow an animal to distinguish itself as a distinct identity. If an animal looks at its own image in a mirror and recognizes "self" rather than identifying the image as another animal, then some investigators interpret this as evidence of cognition. A common test is to modify the visual appearance of an animal (e.g., dying a patch of hair) and then observe the reaction of the animal to its mirror image. If it touches the dyed patch this is taken as evidence for the animal having a concept of "self." Apes, some monkey species, elephants and dolphins, all respond positively in mirror tests, supporting the idea that cognition is important in behavioral development across a broad range of animals (Plotnik et al. 2006).
Social cognition, the ability of an animal to forecast how its own actions will affect its future relationships within a social group, exists in chimpanzees (although it is more limited than in humans) and may extend to other species. In social groups without cognition, behavioral interactions are very much "in the moment," driven by factors such as dominance and family membership. Social cognition allows animals to be more calculating and manipulative in their social relationships. Chimpanzees do not appear to be mean to other members of their social group without justification, but they can, and do, exact revenge against group members that exhibit selfish behavior (Call 2001, Jensen et al. 2006).
Genes and Environment in Human Behavior: Sociocultural
Influences and Politics
An understandable fear
held by many humans is that their behavior is pre-determined by their genes. If
this were the case, a person might be uncontrollably locked into bad parenting,
violent behavior, or drug addiction. Most human cultures hold strong beliefs in self-determination and free will, as well as the ability of humans to separate
right from wrong and to make choices about the appropriateness of their
actions. Heated arguments among biologists, philosophers, religious leaders,
and ethicists over the relative roles of genes and behavior in human behavior
have brought no simple resolution. The evils of eugenics influence many to oppose consideration of any role for genetics
in human behavior. Some biologists have been criticized for underestimating the
role of thought and reasoning in human behavior, while others have been accused
of ignoring the power of evolution in shaping genetically adaptive behavior.
This debate is far from resolved and will continue to fuel controversy, even as
more is discovered about the genetic and evolutionary bases of behavior.
Conclusion
Evolution has acted so
that genes and environment
act to complement each other in
yielding behavioral solutions to the survival challenges faced by animals.
Innate, or instinctive, responses allow animals to benefit from generations of
natural selection on behavior. Learning gives animals tools to respond to local
conditions and changing environments. Understanding the relative roles of genes
and the environment in determining human behavior continues to create
controversy. Behavior is best seen as the result of evolutionary processes that
sometimes create, through genetic coding, behavioral instructions for animals
and at other times create flexible mechanisms to allow animals to solve
problems specific to their environment.
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