Arab Today, arab today living fossil fish sports a lung
Last Updated : GMT 16:25:41
Arab Today, arab today
Arab Today, arab today

Unusual physical traits

'Living fossil' fish sports a lung

Arab Today, arab today

Arab Today, arab today 'Living fossil' fish sports a lung

Coelacanth fossils have been dated to about 400m years ago
Paris - Arab Today

The coelacanth, an elusive deep-sea dweller long thought extinct, had another item added Tuesday to an already-long list of unusual physical traits: an obsolete lung lurking in its abdomen.

Similar to the human appendix, the organ was likely rendered defunct by evolution, researchers noted in the journal Nature Communications.

Like all fish, today's coelacanths -- referred to as "living fossils" -- use gills to extract oxygen from the water they live in.

But millions of years ago, coelacanth ancestors probably breathed using the lung, the team concluded.

"By the Mesozoic Era, adaptation of some coelacanths to deep marine water, an environment with very low variations of oxygen pressure, may have triggered the total loss of pulmonary respiration," co-author Paulo Brito of the Rio de Janeiro State University told AFP.

This could explain how it survived the extinction event 66 million years ago that wiped all non-avian dinosaurs and most other life from Earth -- and probably those coelacanths inhabiting shallow waters, he said.

It would also account for "the marked reduction" of the lung into its shrivelled, present-day form, Brito said by email.

- 'Lazarus' fish -

Coelacanth fossils have been dated to about 400 million years ago, and the fish was thought to have died out towards the end of the Mesozoic era, which stretched from about 250 to 66 million years ago.

But then one was caught off the South African coast in 1938, earning the coelacanth the title of "Lazarus taxon" -- a group of animals "resurrected" from extinction.

A few other individuals have been found since, as well as members of a cousin species off the coast of Indonesia, but the coelacanth is considered endangered.

It is a queer fish in many ways.

Key among its quirks, it has paired, "lobe-shaped" fins which move in an alternating pattern similar to a four-limbed land animal -- sparking speculation that it may have been a member of a group of fish that first crawled onto land to evolve into animals with legs.

The grey-brown fish can grow up to two metres (6.5 feet) in length, weigh as much as 91 kilos (200 pounds), and may live up to 60 years.

It has a hollow, liquid-filled spine, enamel-capped teeth, and a hinged jaw that allows it to open its mouth wide to swallow larger prey.

Little is known about how they live, what they eat, how they reproduce, or how many of them are left.

The new discovery was based on dissections and scans of infant and adult coelacanth samples, as well as 3D reconstructions, said Brito.

The team found that the disfunctional lung is proportionally much larger in the coelacanth embryo than the adult, meaning that growth of the organ slows as the fish gets older.
Source: AFP

 

arabstoday
arabstoday

Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

Arab Today, arab today living fossil fish sports a lung Arab Today, arab today living fossil fish sports a lung

 



Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

Arab Today, arab today living fossil fish sports a lung Arab Today, arab today living fossil fish sports a lung

 



Arab Today, arab today
Arab Today, arab today Designer Aql Faqih aspires to innovation

GMT 18:41 2017 Friday ,20 October

Designer Aql Faqih aspires to innovation
Arab Today, arab today Malaysia Airlines picks new CEO

GMT 12:54 2017 Saturday ,21 October

Malaysia Airlines picks new CEO
Arab Today, arab today Etiquette expert underlines importance of gifts

GMT 17:52 2017 Sunday ,03 September

Etiquette expert underlines importance of gifts
Arab Today, arab today Residents get glimpse of Raqa in ruins

GMT 07:10 2017 Saturday ,21 October

Residents get glimpse of Raqa in ruins
Arab Today, arab today Hiring not part of Alibaba pledge

GMT 11:26 2017 Wednesday ,18 October

Hiring not part of Alibaba pledge
Arab Today, arab today
Arab Today, arab today
Arab Today, arab today World's deepest lake in peril

GMT 15:54 2017 Friday ,20 October

World's deepest lake in peril
Arab Today, arab today Ex-French minister Dati wants tough action

GMT 10:54 2017 Thursday ,19 October

Ex-French minister Dati wants tough action
Arab Today, arab today Delhi braces for pollution 'airpocalypse'

GMT 16:07 2017 Friday ,20 October

Delhi braces for pollution 'airpocalypse'
Arab Today, arab today The history of solar eclipses

GMT 05:16 2017 Sunday ,20 August

The history of solar eclipses
Arab Today, arab today EU raids automaker BMW

GMT 11:06 2017 Saturday ,21 October

EU raids automaker BMW
Arab Today, arab today Sweden to get biggest car factory

GMT 14:10 2017 Friday ,20 October

Sweden to get biggest car factory
Arab Today, arab today Actress Mona Zaki praises husband’s role

GMT 08:15 2017 Thursday ,19 October

Actress Mona Zaki praises husband’s role
Arab Today, arab today Massacre fears spark race

GMT 19:09 2017 Thursday ,19 October

Massacre fears spark race

GMT 08:57 2017 Wednesday ,18 October

Actress Shery Adel happy for Egypt’s qualification

GMT 18:15 2017 Monday ,16 October

British actress becomes fifth woman

GMT 16:53 2017 Tuesday ,05 September

Youssra depended on colored foam

GMT 16:00 2017 Wednesday ,18 October

Climate-disrupting volcanoes helped topple

GMT 10:46 2017 Saturday ,05 August

Nanis reveals simple ideas for home renovation

GMT 09:56 2017 Friday ,20 October

Privacy Groups Warn of Perils

GMT 08:04 2017 Thursday ,19 October

Second US judge orders freeze

GMT 17:12 2017 Monday ,07 August

Al-Shawaifi reveals secrets of total solar eclipse

GMT 20:46 2017 Thursday ,19 October

Qualcomm files lawsuits in China to ban iPhones

GMT 16:53 2017 Saturday ,02 September

Mai importance of gifts during Eid Al-Adha
Arab Today, arab today
Arab Today, arab today
 
 Arab Today Facebook,arab today facebook  Arab Today Twitter,arab today twitter Arab Today Rss,arab today rss  Arab Today Youtube,arab today youtube  Arab Today Youtube,arab today youtube
arabstoday arabstoday arabstoday arabstoday
arabstoday arabstoday arabstoday
arabstoday
بناية النخيل - رأس النبع _ خلف السفارة الفرنسية _بيروت - لبنان
arabstoday, Arabstoday, Arabstoday