How did feathers evolve? - Carl Zimmer

Nola eboluzionatu zuten lumek? - Carl Zimmer

Translator: Andrea McDonough Reviewer: Bedirhan Cinar

Translator: Begoña Laka Reviewer: Jone Aliri Lazcano

Feathers are some of the most remarkable things

Lumak dira animalia batek inoiz sortutako

ever made by an animal.

gauza harrigarrienetako bat.

They are gorgeous in their complexity,

Euren konplexutasuna itzela da

delicate in their construction,

euren eraikuntza delikatua da

and yet strong enough to hold a bird

eta nahiko indartsuak txori bat eusteko

thousands of feet in the air.

ehunka metro airean zehar.

Like all things in nature,

Naturako gauza guztien antzera

feathers evolved over millions of years

lumek milioika urtetan eboluzionatu zuten

into their modern form.

gaur eguneko formara heldu arte.

It could be hard to imagine

Zaila da imajinatzea

how this could have happened.

nola gertatu izan den hau.

After all, what did the intermediate forms look like?

Ze itxura zuten bitarteko formek?

What good is half a wing,

Zertarako balio du hego erdi batek

festooned with half-feathers?

luma erdiak dauzkana?

Thanks to science,

Zientziari esker

we now know that birds are living dinosaurs.

badakigu txoriak direla bizirik dirauten dinosauroak.

You can see the kinship in their skeletons.

Harreman hori eskeletoan ikus dezakezu.

Certain dinosaurs share some anatomical details with birds

Zenbait dinosauroen anatomia-ezaugarriak txorienen antzekoak dira

found in no other animals, such as wish bones.

beste animalietan ez daudenak. Furkula adibidez.

And in the late 1990s,

1990 hamarkadaren amaieran

paleontologists started digging up

paleontologoak ideia horren aldeko frogak ateratzen hasi ziren:

some compelling support for that idea:

dinosaurs with bits of feathers

luma zatien aztarnak

still preserved on their bodies.

gordetzen dituzten dinosauroak.

Since then, scientists have found

Ordutik, zientzialariek dozenaka dinosauro espezie aurkitu dituzte

dozens of species of dinosaurs

with remnants of feathers.

lumen aztarnak dituztenak.

Some were as small as pigeons,

Batzuk usoak bezain txikiak ziren

and some were the size of a school bus.

eta batzuk autobus baten tamainakoak.

If you look at how they are related on a family tree,

Zuhaitz genealogikoan nola lotzen diren ikusten baduzu

the evolution of feathers

lumen eboluzioak ez dirudi hain ezinezkoa.

doesn't seem quite so impossible.

The most distant feathered relatives of birds

Txorien ahaide lumadun urrunenak

had straight feathers that looked like wires.

luma zuzenak zituen, kableen itxurakoak.

Then these wires split apart,

Gero luma hauek banatu egin ziren

producing simple branches.

eta adar sinpleak sortu.

In many dinosaur lineages,

Dinosauro espezie askotan

these simple feathers evolved

luma xume hauek

into more intricate ones,

bihurriagoak bilakatu ziren.

including some that we see today on birds.

Egun, txorietan ikusten ditugu batzuk.

At the same time,

Aldi berean

the feathers spread across the bodies of dinosaurs,

lumak dinosauroen gorputzean hedatu ziren

turning from sparse patches of fuzz

ile-mataza eskas batzuetatik

into dense plumage,

lumaje itxia egin arte

which even extended down to their legs.

hanketatik bera ere zabaldu zena.

A few fossils even preserved some of the molecules

Fosil batzuk lumei kolorea ematen zioten molekulak gorde dituzte

that give feathers color.

They reveal a beautiful range of colors:

Kolore gama ederra erakusten dute:

glossy, dark plumage, reminiscent of crows,

luma ilun, distiratsuak, beleak gogorarazten dituztenak

alternating strips of black and white,

txandakako zerrenda zuri-beltzak

or splashes of bright red.

edo ukitu gorri biziak.

Some dinosaurs had high crests on their heads,

Dinosauro batzuek buruan gandor handiak zituzten

and others had long, dramatic tail feathers.

eta beste zenbaitek luma luze, dramatikoak buztanean.

Now, none of these dinosaurs

Baina dinosauroek ezin zituzten

could use their feathers to fly -

lumak hegan egiteko erabili.

their arms were too short

Beso laburregiak zituzten

and the rest of their bodies were far too heavy.

eta gainerako gorputza astunegia zen.

But, birds don't just use feathers to fly.

Baina txoriek ez dituzte lumak hegan egiteko baino erabiltzen.

A woodcock uses feathers to blend in perfectly

Eperrak lumak erabiltzen ditu

with its forest backdrop.

basoarekin guztiz nahasteko.

An ostrich stretches its wings over its nest

Ostrukak habiaren gainetik zabaltzen ditu hegoak

to shade its young.

bere kumeak estaltzeko.

A peacock displays its magnificent tail feathers

Hegazterrenak bere buztaneko luma zoragarriak

to attract peahens.

emeak erakartzeko darabiltza.

Feathers could have served these functions

Lumek zeregin hauek beteko zituzten

for dinosaurs too.

dinosauroen kasuan ere.

Exactly how feathered dinosaurs took flight

Lumadun dinosauroak hegan egiten nola hasi ziren

is still a bit of a mystery.

oraindik misterioa da.

But if a small-feathered dinosaur flapped

Baina lumadun dinosauro txiki batek

its arms as it ran up an incline,

besoak astindu bazituen aldapan gora korrikan zebilela

its feathers would have provided extra lift

lumek gora bultzatuko zituen

to help it run faster.

eta arinago joaten lagundu.

This accident of physics might have led

Fisikako gertaera honek ekarriko zuen

to the evolution of longer dinosaur arms,

dinosauroen besoak handiago bihurtzea.

which would let them run faster

Horrela, arinago egingo zuten korrika

and even leap short distances through the air.

eta airean zehar salto txikiak egitea lortuko zuten.

Eventually, their arms stretched out into wings.

Azkenik, besoak handituko ziren hego bihurtu arte.

Only then, perhaps 50 million years

Orduan bakarrik, behar bada 50 milioi urte igarota

after the first wiry feathers evolved,

lehengo kable-lumak agertu zirenetik

did feathers lift those dinosaurs into the sky.

lumek, dinosauroak zeruan zehar eraman zituzten.