Early penguins may have used daggers to kiss prey

Four new fossil species of New Zealand illustrate the striking diversity of the first penguins, which had long dagger beaks which they could use to jerk the prey.

The new discoveries “offer an astonishing overview of the first evolution of the penguins”, explains Gerald Mayr at the Senckenberg Research Institute in Germany.

The fossils were unearthed of the Greensand from Waipsa in Canterbury, New Zealand, which contains rocks dating from 62 and 58 million years. The formation is well known for holding some of the first species of birds that prospered and diversified after the mass extinction event which killed all non -avian dinosaurs.

“We believe that a key characteristic of New Zealand ancient was the absence of terrestrial predators, which allowed the loss of flight capacity in the first penguins,” explains Mayr. This lack of predators can also explain why some early penguins have become as large as humans, he says.

In total, Mayr and his colleagues have described four new species, which illustrate a wide diversity of form and size. Many fossils contain skeletal characteristics which were so far unknown, including a specimen with abnormally long rear toes and another which had the most remarkably complete skull and beak of any early penguin.

“Fossils containing beaks, which may indicate the diet of a bird, are extremely rare for penguins of the periods before [23 million years ago]”Said Tatsuro Ando at the Ashoro Paleontology Museum in Japan, which was not involved in the study.

Living penguins have a variety of beak forms that are adapted to the specific prey they consume, which can go from Krill and small fish to invertebrates like Calmar, explains Ando. These spouts can be short, thick or curved, but none of these spins are comparable to those found in early penguins, which are long and straight.

“The first penguins seem to have launched their prey with long beaks,” explains Mayr. After kissing a fish, the penguin may have resurfaced the water to throw it in the air and catch it, he said.

Penguins lost their elongated spouts after about 20 million years, which was probably an adaptation to the periods of diving underwater. As they adopted a more aquatic lifestyle, their food strategies and their beak also started to change.

The new fossils help to show that New Zealand was the “cradle of the evolution of penguins”, explains Mayr, and the first diversified and dispersed penguins of New Zealand in the world such as Antarctica, South Africa and a large part of South America.