Diff13 - 13 Flashcards
Why will a fruit fly benefit from rapid development?
Laying eggs on rotting fruit means flies must hatch and develop before fruit completely disintegrates
What is the phylotypic stage?
Point at which all mammals are fairly similar
Outline developmental changes around the phylotypic stage
Before - reproductive adaptations caused changes; after - these are species specific
How does evolution develop a new feature?
It doesn’t de novo - only ever modifies existing structure
Where did limbs evolve from?
Fins, 360-400m years ago
Characterise Darwin’s finches
From Galapagos, common ancestor, beaks different based on food source
What determines no. of neck vertebrae?
Hox6
What represses wing development?
Ubx
What is heterochrony?
Changes in relative timing of developmental processes
Examples of heterochrony
Dogs’ noses, horses’ feet, marsupials’ anterior limb
What is neoteny?
Reaching sexual maturity in a larval stage
Give an example of neoteny
Axolotl
What happened evolutionarily 100myr?
Dorsal/ventral switch in chordates
