Luciano Candisani / Treefrog (Dendropsophus elegans) on fern, Atlantic Forest, Brazil

Claus Meyer / Tree Frog (Hyla sp) balanced on fern fiddlehead, Atlantic Forest, Brazil

Staffan Widstrand / Wild Wonders of China / Ostrich or Fiddlehead fern (Matteuccia struthiopteris) growing in Tangjiahe National Nature Reserve, Sichuan, China

Floris van Breugel / Common polypody fern / fiddlehead (Polypodium vulgare) fronds unfurling, Olympic National Park, Washington, USA. May 2012.

Scott Leslie / Unfurling fern in spring woods, Nova Scotia, Canada

Hiroya Minakuchi / Fern fiddlehead, Danum Valley, Malaysia

Pete Oxford / Fern frond fiddlehead unfurling in lower temperate forest, Ecuador

Pete Oxford / Fern frond fiddlehead unfurling in lower temperate forest, Ecuador

Jerry Monkman / Common polypody fern / fiddlehead {Polypodium vulgare} frond unfurling, Boxford, Massachusetts, USA

Jerry Monkman / Common polypody fern / fiddlehead {Polypodium vulgare} frond unfurling, Boxford, Massachusetts, USA

Thomas Marent / Young rolled-up fern fiddlehead, Braulio Carrillo National Park, Costa Rica

Thomas Marent / Fern fiddleheads, Sabah, Borneo, Malaysia

Thomas Marent / Fern tip curled up, Yanachaga-Chemellin National Park, Peru

Scott Leslie / Unfurling springtime ferns, Nova Scotia, Canada

Scott Leslie / Unfurling springtime fern, Nova Scotia, Canada

Ingrid Visser / Tree Fern fiddlehead unfurling, New Zealand

Harley Betts / Fern fronds unfurling, Depot Creek, Haast Valley, Mt. Aspiring National Park, New Zealand

Harley Betts / Tree Fern (Dicksonia sp) unfurling fiddlehead frond, Punakaiki, New Zealand

Ingo Arndt / Fern fiddleheads rolled up, highlands, Malaysian Peninsula

Jan Vermeer / Bracken Fern (Pteridium aquilinum) young fiddleheads opening

Konrad Wothe / Tree Ferns, South Island, New Zealand

Pete Oxford / New fern head with protective gelatinous coating, Mindo cloud forest, Ecuador

Gerry Ellis / Deer Fern (Blechnum spicant) fiddleheads, Vancouver Island, British Columbia, Canada

Gerry Ellis / Tropical rainforest interior with Ficus tree and buttressed roots, Malaysia

Claus Meyer / Tree Frog (Hyla sp) perching atop Fern fiddlehead, Atlantic Forest ecosystem, Brazil

Scott Leslie / Fern (Adiantaceae) fiddlehead, Cape Breton Island, Nova Scotia, Canada

Konrad Wothe / Male Fern (Dryopteris filix-mas) new growth of fiddleheads, Upper Bavaria, Germany

Gerry Ellis / Deer Fern (Blechnum spicant) fiddleheads, Pacific coast, North America

Murray Cooper / Fern frond unfolding, Ecuador

Ross Hoddinott / Small pearl-bordered fritillary butterfly (Boloria selene) roosting on Hard fern (Blechnum spicant) fiddlehead. Marsland Valley Wildlife Trusts Reserve, Cornwall, England, UK. June.