Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Otago researchers reveal new NZ fossil dolphin

Otago researchers reveal new NZ fossil dolphin


A newly recognised fossil dolphin from New Zealand, dubbed Papahu taitapu, is the first of its kind ever found and may be a close relation to the ancestors of modern dolphins and toothed whales, according to University of Otago researchers.

Papahu lived 19–22 million years ago, and is one of the few dolphins to be reported globally dating to the start of the Miocene epoch. Judging from the size of its skull, Papahu was about two metres long, roughly the size of a common dolphin.

Dr Gabriel Aguirre and Professor Ewan Fordyce, from the University’s Department of Geology describe and interpret Papahu in the latest issue of Journal of Vertebrate Paleontology. This work was part of Dr Aguirre’s PhD research.

Dr Aguirre says that like most living dolphins, Papahu had many simple conical teeth, but its head was probably a bit wider, and not as high-domed. It lived at a time of global warmth, in shallow seas around Zealandia – or proto-New Zealand – along with ancient penguins and baleen whales.

The skull, one jaw, and a few other parts of Papahu taitapu were found in marine sedimentary rocks in the Cape Farewell region of northern South Island. The researchers used the Māori name ‘taitapu’ to honour this region, and ‘Papahu’ is a Māori name for dolphin. Only a single specimen has been found so far and the fossil is housed in the University’s Geology Museum.

“Our study of structures of the skull and earbone suggest that Papahu could make and use high frequency sound to navigate and detect prey in murky water. They probably also used sound to communicate with each other,” says Dr Aguirre.

Features of the Papahu skull can be used to analyse relationships with other dolphins and toothed whales. That work shows that the skull is distinct from all previously-reported fossils, which is why the dolphin can be formally named as a new form, he says.

“When we compared Papahu with both modern and fossil dolphins we found that it belongs in a diverse and structurally variable group of ancient dolphins that evolved and spread world-wide 19–35 million years ago. All of those ancient dolphins including Papahu and others, such as shark-toothed dolphins, are now extinct,” says Professor Fordyce.

“They have been replaced by the ‘modern’ dolphins and toothed whales, which diversified within the last 19 million years,” he says.

It is not clear, however, exactly why Papahu and other ancient dolphins went extinct, he added.

ends

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Budget Policy Statement: Spending Wins Over Tax Cuts; Big Ticket Items Get Boost

Income tax cuts are on hold as the government says “responding to the earthquakes and reducing debt are currently of higher priority”, although election year tax sweeteners remain possible. More>>

ALSO:

Fishy: Is Whitebaiting Sustainable?

The whitebait fry - considered a delicacy by many - are the juveniles of five species of galaxiid, four of which are considered threatened or declining. The SMC asked freshwater experts for their views on the sustainability of the whitebait fishery and whether we're doing enough to monitor the five species of galaxiid that make up whitebait. More>>

ALSO:

Crown Accounts: Smaller-Than-Expected Four-Month Deficit

The New Zealand government's accounts recorded a smaller-than-forecast deficit in the first four months of the fiscal year on a higher-than-expected inflow of corporate and goods and services tax. More>>

ALSO:

On For Christmas: KiwiRail Ferries Back In Full Operation After Quake

KiwiRail’s Interislander ferries are back in full operation for the first time since the Kaikoura earthquake, with the railspan that allows rail wagons to be loaded on the Aratere now restored. More>>

ALSO:

Comerce Commission Investigation: Prosecutions Over Steel Mesh Labelling

Steel & Tube Holdings, along with two other companies, will be prosecuted by the Commerce Commission following the regulator's investigation into seismic steel mesh, while Fletcher Building's steel division has been given a warning. More>>

ALSO:

Wine: 20% Of Marlborough Storage Tanks Damaged By Quake

An estimated 20 percent of wine storage tanks in the Marlborough region, the country’s largest wine producing area, have been damaged by the impact of the recent Kaikoura earthquake. More>>

ALSO:

ACC: Levy Recommendations For 2017 – 2019 Period

• For car owners, a 13% reduction in the average Motor Vehicle levy • For businesses, a 10% reduction in the average Work levy, and changes to workplace safety incentive products • For employees, due to an increase in claims volumes and costs, a 3% increase in the Earners’ levy. More>>

Get More From Scoop

 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news