Sex and Death Chapter 5: The developmental systems alternative

5.1 Developmental Systems Theory –no privileged class of replicators

Step 1: not only genes are inherited

Step 2: genes are not determining traits

Step 3: not only genes contain “information”

Step 4: no exclusive role for genes in development

Step 5: genes are not special molecules

Sex and Death Chapter 5: The developmental systems alternative

5.2 epigenic inheritance and beyond:

organism inherit

- behavioral repertoires

- epigenic inheritance systems

- extracellular structures

not only gens

Sex and Death Chapter 5: The developmental systems alternative

5.3 the interactionist consensus:

all traits have both - genetic and - nongenetic causes,

so genes cannot be separated as playing a determining role.

Sex and Death Chapter 5: The developmental

systems alternative

Genes are “context-sensitive difference makers”

They produce their effects by adding a physical product to a complex network of causes consisting

- of other genes and their immediate products- the other constitutes of the initial cell- all the inputs of materials and energy to the

developing organism.

Sex and Death Chapter 5: The developmental systems alternative

5.4 information in development:The causal notion of information:Information flows over a channel connecting two systems:- The receiver: the system that contains the information- The sender: the system that the information is about. When we can infer the state of the sender from the state

of the receiver, then the systems are systematically causally related.

However, in order to make sense of gene”s malfunctioning, an intentional notion of information is necessary.

Sex and Death Chapter 5: The developmental systems alternative

5.4 information in development:The intentional notion of information:The relation between gene and organism is like the one

between thought and thing.

Susan Oyama: The whole notion of developmental information should be abandoned

the development in the embryo relies on cues in the developmental environment. There is no developmental plan within the embryo.

Sex and Death Chapter 5: The developmental systems alternative

- In any sense in which genes carry information, nongenetic developmental factors carry developmental information too.

Sex and Death Chapter 5: The developmental systems alternative