Dogs mercury

Landscape showing an ancient oak woodland with oak trees which were last pollarded years ago, the under storey is carpeted with bluebells, the trees are hung with lichen, and there are moths in the foreground settled on a patch of wild spring flowers

Bluebell wood with the spring flowrs carpeting the forest floor, in the foreground a male redstart perches on a tree stump with lichen, behind are some butterflies and a pied flycatcher perches on the wooden bridge walkway that covers an area of boggy ground, beyond the path stretches away into distant airy woodland and sunlight

Vertebrate embryos comparing growth forms in chart form