Weird Science

with Her­ald science writer Jamie Mor­ton: @jamien­zher­ald

Weekend Herald - - Science & Tech -

How did Aussie get its snakes?

Ever won­der where Aus­tralia’s deadly snakes slith­ered in from?

A new study is help­ing sci­en­tists ex­plain how they de­scended from crea­tures that came from Asia over the past 30 mil­lion years.

Aus­tralian Na­tional Uni­ver­sity’s Dr Paul Oliver says about 85 per cent of more than 1000 snake and lizard species in Aus­tralia de­scended from crea­tures that floated across wa­ters from Asia to Aus­tralia.

The re­search helps ex­plain how Aus­tralia has be­come home to about 11 per cent of the world’s 6300 rep­tile species — the high­est pro­por­tion of any coun­try.

“Around 30 mil­lion years ago it ap­pears that the world changed, and sub­se­quently there was an in­flux of lizard and snakes into Aus­tralia,” Oliver says.

“We think this is linked to how Aus­tralia’s

rapid move­ment north, by con­ti­nen­tal move­ment stan­dards, has changed ocean cur­rents and global cli­mates.”

The re­searchers con­ducted the study us­ing an­i­mal tree-of-life data com­bined with em­pir­i­cal ev­i­dence and sim­u­la­tions.

The ori­gins for rep­tiles con­trast with other Aus­tralian an­i­mal groups in­clud­ing mar­su­pi­als and birds, which in­clude many more species de­scended from an­ces­tors that lived on Gond­wana, a su­per con­ti­nent that in­cluded Aus­tralia, Antarc­tica, South Amer­ica, Africa and Mada­gas­car.

Oliver says the study has found that the im­mi­gra­tion of rep­tiles into Aus­tralia was clus­tered in time.

“The in­flux of lizards and snakes into Aus­tralia cor­re­sponds with a time when fos­sil ev­i­dence sug­gests an­i­mal and plant com­mu­ni­ties un­der­went ma­jor changes across the world,” he says.

“The move­ment of Aus­tralia may have been a key driver of these global changes.”

Down­load­ing data — to your clothes

A new smart fab­ric could pave the way for jack­ets that store in­vis­i­ble pass­codes and open the door to your home or of­fice.

US com­puter sci­en­tists have cre­ated fab­rics and fash­ion ac­ces­sories that can store data — from se­cu­rity codes to iden­ti­fi­ca­tion tags — with­out need­ing any on-board elec­tron­ics or sen­sors.

The Uni­ver­sity of Wash­ing­ton team has used pre­vi­ously un­ex­plored mag­netic prop­er­ties of off-the-shelf con­duc­tive thread.

The data can be read us­ing an in­stru­ment em­bed­ded in a smart­phone to en­able nav­i­ga­tion apps.

“This is a com­pletely elec­tronic-free de­sign, which means you can iron the smart fab­ric or put it in the washer and dryer,” study au­thor As­so­ciate Pro­fes­sor Shyam Gol­lakota says.

“You can think of the fab­ric as a hard disk — you’re ac­tu­ally do­ing this data stor­age on the clothes you’re wear­ing.”

Most peo­ple com­bine con­duc­tive thread — em­broi­dery thread that can carry an elec­tri­cal cur­rent — with other types of elec­tron­ics to cre­ate out­fits, stuffed an­i­mals or ac­ces­sories that light up or com­mu­ni­cate.

But the re­searchers re­alised this off-theshelf con­duc­tive thread has mag­netic

prop­er­ties that can be ma­nip­u­lated to store dig­i­tal data or vis­ual in­for­ma­tion such as let­ters or num­bers.

This data can be read by a mag­ne­tome­ter, an in­ex­pen­sive in­stru­ment that mea­sures the di­rec­tion and strength of mag­netic fields and is em­bed­ded in most smart­phones.

“We are us­ing some­thing that al­ready ex­ists on a smart­phone and uses al­most no power, so the cost of read­ing this type of data is neg­li­gi­ble,” Gol­lakota says.

The fab­ric can be re­mag­ne­tised and re­pro­grammed mul­ti­ple times and a fab­ric patch re­tained its data even af­ter ma­chine wash­ing, dry­ing and iron­ing at tem­per­a­tures of up to 160C.

The team also says the mag­ne­tised fab­ric could be used to in­ter­act with a smart­phone while it is in a pocket. “We can eas­ily in­ter­act with smart de­vices with­out hav­ing to con­stantly take them out of our pock­ets,” lead au­thor Justin Chan says.

Pic­ture / Den­nis Wise, Uni­ver­sity of Wash­ing­ton

Pic­ture / 123RF

Newspapers in English

Newspapers from New Zealand

© PressReader. All rights reserved.