Acting Brazilian President Michel Temer has opened the 2016 Summer Olympic Games at the Maracana stadium in Rio de Janeiro, Brazil, as the country grapples with an economic and political crisis.

There were jeers and booing from the audience as the 75-year-old politician, who stepped up from the post of vice-president and replaced suspended President Dilma Rousseff, declared open the first Games ever in South America.

He was flanked by dozens of heads of state and spoke just a few words. A loud round of fireworks was set off to obscure the cat calls as soon as he finished speaking. The opening ceremony was decidedly simple and low-tech, clearly pointing to Brazil’s financial woes.

The opening ceremony began with a demonstration of the beginning of life itself in Brazil, and the population that formed in lush rainforests and set up their communal huts, commonly known as the ocas.

The ceremony then gave a picture of the arrival of the Portuguese and their conquest of the indigenous people, before African slave laborers rolled in on wheels and was used to plow through forests and modernize rustic Brazil.

Brazilian officials also used the Olympics opening ceremony to call an estimated three billion people watching the high-status sporting event worldwide to take care of the planet, plant seeds and protect the Amazon.

Each athlete will be asked to plant seeds that will eventually grow into trees. The trees will then be planted in the Athletes Forest in Rio within the next few years. Brazilian runner Vanderlei Cordeiro de Lima lit the Olympic cauldron at the opening ceremony.

Retired former World No. 1 tennis player Gustavo Kuerten, also known as Guga, kicked off the cauldron relay, handed over the torch to the world’s great female basketball player Hortencia Marcari. She then passed it to Cordeiro.

Earlier, Thomas Bach, the president of the International Olympic Committee, called on world nations to unite amidst ongoing conflicts in the world. “We are living in a world of crises, mistrust and uncertainty,” he said.

“Here is our Olympic answer: the 10,000 best athletes in the world, competing with each other, at the same time living peacefully together in one Olympic Village, sharing their meals and their emotions.

“In this Olympic world, we see that the values of our shared humanity are stronger than the forces which want to divide us,” Bach said.

Even though Brazilian authorities have not disclosed how much has been spent on preparations for the Games, it is believed that Rio has spent about half of the $42 million that London spent on the Games in 2012.

Not more than 750 meters away from the Maracana stadium that has had more than $500 million spent on it in the past two years, some of the poorest people in Brazil are living in destitution and lack proper sanitation, health care, education as well as security due to drug violence.

Rousseff, the suspended president, was supposed to preside over the Rio 2016 Olympic Games, but Brazil’s upper chamber of the National Congress voted in May to suspend her and begin an impeachment trial against her.

The impeachment bid was launched over allegations that she manipulated government accounts before the last election. She, however, strongly denies the allegations.