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Some elephants are evolving to have no tusks as a response to brutal poaching

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This image of a tranquilised tuskless female elephant in Mozambique’s Gorongosa National Park was taken while genetic samples were collected in 2018.

An elephant’s tusks are among its defining features — they help the animal lift heavy branches, topple trees, strip bark, fight, and dig holes for water and minerals.

But an increasing proportion of elephants in Mozambique’s Gorongosa National Park have been born without these crucial tools, and scientists say it is an evolutionary response to the brutal killing of elephants for their ivory tusks during the country’s 15-year civil war.

Elephant experts working in the park had begun to notice the phenomenon after the war ended in 1992. Field data and analysis of old video footage from the park found that the proportion of tuskless female elephants increased more than threefold between 1972 and the year 2000. It was a period during which the elephant population plummeted from roughly 2,000 to about 250 individuals, said Ryan Long, an associate professor of wildlife sciences at the University of Idaho.

“During the war, Gorongosa was essentially the geographic centre of the conflict,” Long said via email. “As a result there were large numbers of soldiers in the area and a lot of associated motivation… to kill elephants and sell the ivory to purchase arms and ammunition. The resulting level of poaching was very intense.”

Genetic signature

Scientists now have a better understanding of the genetic basis for this tusklessness and why it only appears to affect female elephants, according to a study that published in the journal Science on Thursday.

The analysis showed that tuskless females were over five times more likely to survive during the 28-year period than their tusked female counterparts, hence the adaptation was very unlikely to be a chance occurrence.

Tusklessness does occur naturally — and only in females — even in the absence of poaching, but usually only in a small minority of elephants. In Gorongosa in the 1970s, 18.5% of female elephants didn’t have tusks, while three decades later 51% did.

“Evolution is simply a change in heritable characteristics within a population over successive generations, and based on the results of our study, the shift toward tusklessness among female elephants at Gorongosa fits this definition perfectly,” said Long, an author of the study.

“The fact that it occurred so rapidly is rare indeed, and is a direct function of the strength of selection,” he said via email. “In other words, it happened so quickly because tuskless females had a MUCH higher probability of surviving the war, and thus a MUCH greater potential for passing their genes on to the next generation.

But what about the male elephants? After taking blood samples of 18 female elephants, with and without tusks, the researchers sequenced their genomes. They found that the females with no tusks had a genetic variation in a very specific region of the X-chromosome, which plays a role in tusk development.

“Females have 2 X chromosomes. In tuskless females, one of those chromosomes is ‘normal’ and the other contains the deleted information,” Long explained.

“When a tuskless female conceives a male offspring, that male has a 50/50 shot of receiving the affected X-chromosome from its mother. If it receives the ‘normal’ chromosome then it will survive and be born with the necessary genetic information to produce tusks.”

However, if the male elephant fetus receives the chromosome with the genetic variant, it dies in the womb because the variant that produces tusklessness females is lethal to males, Long said.



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Countrywide power outage act of sabotage, claim TU, officials

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Unions suspect sinister attempt to call in military

Engineers say technical fault caused power failure

CEBEU suspends work-to-rule protest

By Ifham Nizam

The government was trying to pin the blame for yesterday’s countrywide power outage on the Ceylon Electricity Board (CEB) trade unions in a bid to call in the military, Joint Trade Union Alliance Convener Ranjan Jayalal said yesterday.

Jayalal told The Island the government’s attempt would tarnish the image of the military and that of the country, but such intimidatory tactics would not deter the CEB unions from continuing with their action against the questionable agreement between the government and the US energy firm, New Fortress, which has been allowed to acquire a 40% stake in the Yugadanavi power plant. “The government is trying to derail our trade union action, scheduled for December 08. Definitely the power outage was an act of sabotage. Two units of the Norochcholai coal-fired power plant and the one at Sapugaskanda had failed,” he added, insisting that the trade unions had nothing do with the power outage. He said union activists had sprung into action to restore power despite their work-to-rule, for the sake of the country and its people.

A senior independent electrical engineer said the power failure was an act of sabotage or attempt at sabotage. “It could have been a rehearsal that misfired,” he added.

Electricity supply in several areas in Colombo and its suburbs were restored around 2.00 p.m. Subsequently, the power supply on Anuradhapura-Habarana, Laxapana-Athurugiriya and Kotmale-Biyagama transmission lines was restored. However, even at 5.30 p.m. most parts of the Gamapaha District experiencing power failures.

CEB General Manager, Eng. M R Ranatunga sand disruptions to the power supply could be considered sabotage. He said CEBEU activists had been dragging their feet on power restoration.

State Minister of National Security & Disaster Management Chamal Rajapaksa said necessary action would be taken against the CEB engineers if it was revealed that the power outage was an act of sabotage.

Major disruptions to the electricity supply were reported across the country around 11.30 a.m. yesterday owing to a breakdown in transmission lines.

The National Water Supply and Drainage Board (NWS&DB) said the water supply in several areas of Colombo and suburbs had been disrupted due to the breakdown in the power supply as the NWS&D is dependent on the national grid for pumping purposes.

The Ceylon Electricity Board Engineers Union (CEBEU) last night said it had received a favourable response from the government to its demands and therefore decided to suspend its work-to-rule campaign.

The Island learns that President’s Secretary Dr. P. B. Jayasundara will meet a CEBEU delegation, next week.

A senior electrical engineer expressed concern about CEB General Manager’s statement that the power outage was an act of sabotage by the engineers’ union. He denied as baseless the official’s claim.

CEBEU Secretary Dhammike Wimalarathne confirmed that his union had decided to suspend trade union action following an undertaking given by the government to have talks with them.

Meanwhile, CEBEU President Saumya Kumarawadu, addressing the media, yesterday, insisted that the power outage had been due to a technical problem.

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Chamal tells Parliament if power failure is due to sabotage, culprits will be dealt with severely

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By Saman Indrajith

Minister of Irrigation and State Minister of Internal Security, Home Affairs and Disaster Management, Chamal Rajapaksa told Parliament yesterday that the government was investigating the causes of yesterday’s countrywide power outage and if it was due to sabotage those responsible would be severely dealt with.

Responding to a question by Anuradhapura District SJB MP Rohana Bandara Dissanayake during the third reading stage debate on Budget 2022 under the expenditure heads of the Ministry of Defence, the Minister said that the government would not tolerate sabotage.

MP Rohana Bandara Dissanayake said that while the national security was being debated in Parliament the entire country was experiencing a power outage which could be considered a serious threat to national security.

He said all reservoirs were brimful and there was sufficient water to generate hydro power.

Colombo District SJB MP Dr. Harsha de Silva said that the entire country was in dark and Parliament was sitting thanks to power supplied by generators.

Minister Rajapaksa said that the government had already called for an investigation and it would not hesitate to take necessary action on the findings of the probe.

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Committee on Public Finance meeting: one-third drop in next Yala harvest predicted

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Members of the Committee on Public Finance recently recommended that if the import ban on rice, which was imposed last April, is to be lifted, it should be done only after a proper forecast of the coming Yala harvest.

The Chairman of the Committee on Finance Anura Priyadharshana Yapa pointed out that under the prevailing circumstances, the interest of the paddy farmers and consumers had to be taken into consideration.

In response to MP Yapa’s comment, the Imports and Exports Controller General revealed that, according to the available data, the expected Yala harvest is likely to be only 2/3 as compared to last year.

MP Nalin Fernando pointed out that if businessmen were allowed to import rice freely, the business community would be tempted to import more rice than necessary, driving the paddy prices down and affecting the farming community badly. Hence, the Ministry of Finance should intervene to prevent the local farmer from facing difficulties. MP Fernando also pointed out to the officials of the Ministry of Finance that it was important to make rice freely available at reasonable prices. Sri Lankans did not like rice imported from neighbouring countries, he said.

The Committee on Public Finance was urged to obtain approval for an Extraordinary Gazette Notification permitting the importation of Kekulu, Nadu, Samba and other types of rice as per the order of the Minister of Finance. MP Dr. Harsha de Silva said officials had to investigate the macro economic impact of such orders given without a proper procedural or logical assessment.

The committee members inquired from the officials of the Ministry of Finance who were present at the Committee meeting whether the 2021 Budget forecasts could be fulfilled. According to the statistics and data submitted by the officials of the Ministry of Finance, the committee observed that if only local funds were used to repay all debts, there would be an increase in interest rates in the near future and that would adversely affect the local private sector, (Dr.) Harsha de Silva said.

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