Page 17 - HOH

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CLASSIFIED Saturday 3 auguSt 2019

Scientists get peek into how some fish HEALTH

change sex as adults DOCTOR ON DUTY

Oranjestad
By JEREMY REHM Hospital 7:00 pm / 10:00pm
Associated Press Tel. 527 4000
NEW YORK (AP) — If in the San Nicolas
beginning there was male IMSAN 24 Hours
and female, fish seem to Tel.524 8833
have forgotten the memo. Women in Difficulties
For nearly 500 fish species, PHARMACY ON DUTY
including the clownfish in
"Finding Nemo," the great Oranjestad:
divide between sexes is Oduber Tel. 582 1780
San Nicolas:
more like a murky line: If cir- San Nicolas Tel. 584 5712
cumstances call for it, the Women in Difficulties
fish can swap their sex, with OTHER
females turning into males Dental Clinic 587 9850
in some species and males Blood Bank Aruba 587 0002
turning into females in oth- Urgent Care 586 0448
ers. Walk-In Doctor’s Clinic
+297 588 0539
People think of sex as be- In this photo provided by Kevin Bryant, a dominant male blue- Women in Difficulties
ing fixed, said biologist Eri- head wrasse, upper left, defends its spawning territory and a EMERGENCY
ca Todd from the University group of females, yellow, off the coast of Florida. Police 100
of Otago in New Zealand, Associated Press Oranjestad 527 3140
"but there are so many fish Noord 527 3200
that can push it in the other follow what was happen- rangement of chemical Sta. Cruz 527 2900
direction." ing at the genetic level. tags that attach to DNA. San Nicolas 584 5000
Scientists have known for They found that removing These tags turn genes on Police Tipline 11141
decades about the sex the males likely stressed or off and have specific ar- Ambulancia 911
trades, but they've had lim- females. The hormones re- rangements in males and Fire Dept. 115
Red Cross
582 2219
ited understanding of how leased from that stress dial females. As female wrasse
the exchange happens. In back the activity of the transitioned to a male, TAXI SERVICES
a study published Wednes- gene that makes the fe- these tags were removed Taxi Tas 587 5900
day in Science Advances, male hormone estrogen, and reorganized, almost as Prof. Taxi 588 0035
Todd and her colleagues and eventually ovary cells if the fish was being repro- Taxi D.T.S. 587 2300
detail the molecular events start to die. At the same grammed. Taxi Serv. Aruba 583 3232
behind this ability, as well time, those hormones in- "They're sort of poised and A1 Taxi Serv. 280 2828
as what keeps mammals crease activity in the genes ready to go either direc- Women in Difficulties
stuck as one sex or another. that produce male hor- tion" like a seesaw, she said. TRAVEL INFO
The researchers looked mones, and later testicles The hormones help push it Aruba Airport 524 2424
at the bluehead wrasse, form. to the male side. American Airlines 582 2700
a reef fish that swims in At a certain point, the re- Laura Casas, a biologist in Avianca 588 0059
small groups of a dominant productive gland "is most- Spain who was not involved Jet Blue 588 2244
blue-headed male and a ly dying female cells and in the study, called the re- Surinam 582 7896
posse of smaller yellow fe- proliferation of early male sults surprising. She expects
males. Normally the male cells," Todd said. the findings can apply to Women in Difficulties
and females stay as they But hormones weren't other sex-changing fish, in- CRUISES
are, feeding together and the only thing switching cluding her study animal
occasionally mating. But around. The scientists also clownfish, which shift from
if a predator happens to saw a complete rear- male to female.q
snatch up the lead male,
the dominant female in the
group will become a male. August 4
Freewinds
"The sex change in this spe- August 7
cies is remarkable because Monarch
Women in Difficulties
it's so quick," Todd said. Freewinds
It takes only minutes to a AID FOUNDATIONS
few hours for the female's FAVI- Visually Impaired
behavior to become more Tel. 582 5051
territorial and aggressive
like a male. In a few days, Alcoholics Anonymous
Tel. 736 2952
she courts other females. Narcotics Anonymous
And after eight to 10 days, Tel. 583 8989
she's fully transitioned to a Women in Difficulties
male. Tel. 583 5400
Todd and her team re- Centre for Diabetes
moved the lead males from Tel. 524 8888
several wrasse groups in Child Abuse Prevention
Tel. 582 4433
the Florida Keys. As the fe-
males changed sexes, the Quota Club Tel. 525 2672
Women in Difficulties
researchers took DNA from General Info
cells in the animal's brains
and genitals so they could Phone Directory Tel. 118