The logic of monsters: development and morphological diversity in stem-cell-based embryo models

Area of Science:

• Developmental biology
• Evolutionary developmental biology (Evo-Devo)
• Stem cell research

Background:

• Organoids and stem-cell-based embryo models (SEMs) offer expanded views of biological form (morphospace) compared to in vivo systems.
• Early evo-devo work, particularly Pere Alberch's concept of 'the logic of monsters,' provides a framework for interpreting aberrant development.

Purpose of the Study:

• To interpret SEMs through the lens of Alberch's developmental "monstrosities" to understand developmental constraints.
• To explore how SEMs can illuminate fundamental principles of normal embryonic development.

Main Methods:

• Conceptual analysis integrating SEM biology with Alberch's evo-devo principles.
• Discussion of SEMs as experimental tools for exploring morphospace and developmental rules.

Main Results:

• SEMs, viewed as "monstrosities," reveal insights into developmental variability, internal vs. external constraints, boundary conditions, and robustness.
• The "monstrosity" of SEMs is proposed as a key to uncovering hidden developmental constraints and patterning rules.

Conclusions:

• SEMs are powerful tools for expanding the exploration of developmental morphospace.
• Leveraging the aberrant nature of SEMs can uncover fundamental, often hidden, rules governing embryonic development and robustness.