Developmental Stages

Carnegie Stage 1

Fertilization of Egg

Carnegie Stage 2

First cleavage through morula

Carnegie Stage 3

Unimplanted blastocye

Carnegie Stage 4

Shedding of zona pellucida

Carnegie Stage 5

Implantation is complete

Carnegie Stage 6

Gastrulation Begins

Carnegie Stage 7

cell migration defining gastrulation

Carnegie Stage 8

appearance of neural plate and neural groove

Carnegie Stage 9

Somites appear on either side of the neural groove

Carnegie Stage 10

formation of neural tube

Carnegie Stage 11

more somites grow

Carnegie Stage 12

neural tube closes

Carnegie Stage 13

30 pair of somites

Carnegie Stage 14

rapid brain growth

Carnegie Stage 15

cerebral hemispheres can be discerned

Theiler Stage 1

Fertilization

Theiler Stage 7

blastocyte sheds zona pellucida and implants

Theiler Stage 11

appearance of neural plate and groove

Theiler Stage 12

portion of neural tube closes

Theiler Stage 14

anterior portion of tube closes

Theiler Stage 15

posterior neuropore forms

Theiler Stage 16

posterior neuropore closes

Theiler Stage 18

rapid brain growth

Danio Rerio Stage 1

Early blastula

Danio Rerio Stage 2

midblastula

Danio Rerio Stage 3

early gastrula

Danio Rerio Stage 4

mid gastrula

Danio Rerio Stage 5

early segmentation

Danio Rerio Stage 6

mid segmentation

Danio Rerio Stage 7

pharyngula

Bownes Stage 1-3

unusual cleavage

Bownes Stage 4

syncytical blastoderm

Bownes Stage 5

cellular blastoderm

Bownes Stage 6

gastrulation

Bownes Stage 7

germ band elongates

Bownes Stage 9

neuroblasts form

Bownes Stage 11

delamination of neuroblasts

Bownes Stage 12

body segments visible

Bownes Stage 13

germ band retracts

C. Elegans

Fertilized → L1 → L2 → L3 → L4 → Adult