Maussan shared on social media and in his presentation the results of DNA and carbon dating tests that he said he commissioned on "the beings."
A Mexican scientist, at the request of Reuters, reviewed the results and concluded they indicated normal life on Earth.
Maussan told Reuters on Friday that the test results were not directly related to the two bodies that he showed Congress this week, however. In fact, he said, they were conducted on an entirely different body, known as Victoria, that remains in Peru.
"They were found in the same place. They have the same physical appearance, they are the same," Maussan said of Victoria and the two bodies he presented in Mexico. Testing was not done on those two bodies in order to avoid damaging them, he said.
Maussan is no stranger to controversy. He has made claims about other remains in the past that have been widely criticized. He participated in a 2017 TV documentary about other remains found near the Nazca Lines, which experts like Tomasto-Cagigao and paleontologist Rodolfo Salas-Gismondi have said appeared to feature doctored mummies.
Now, he has angered Peruvian officials.
Peruvian Culture Minister Leslie Urteaga has questioned how the specimens, which she said were pre-Hispanic objects, left Peru and says a criminal complaint has been filed.
"I'm not worried. I have done absolutely nothing illegal," Maussan said.
How the bodies arrived in Mexico is a question he says he cannot answer. Borrowed by Maussan for the hearing, they are in the possession of a Mexican man, who was in Maussan's office on Friday and who declined to be identified.
When asked how the bodies - whom he called Clara and Mauricio - came to be in his possession, the man replied only that he would reveal all "at the appropriate time."
Jose de Jesus Zalce Benitez, Director of the Health Sciences Research Institute of the Secretary of the Navy, participated in the congressional hearing, bolstering Maussan's claims. Now joining him at his office, he calmly explained his interpretation of the science.
"Based on the DNA tests, which were compared with more than one million species ... they are not related to what is known or described up to this moment by science or by human knowledge," he said.
Julieta Fierro, the scientist at Mexico's National Autonomous University's (UNAM) Institute of Astronomy who reviewed Maussan's test results for Reuters, sees far less mystery in the data.
She said that the presence of carbon-14 in studies done by UNAM proves that the samples were related to brain and skin tissues from different mummies who died at different times.
The proportion of the radioactive carbon-14 isotope that is absorbed by living organisms into their tissue decays over time, which allows scientists to determine the approximate year of death of the specimen.
On other planets, the amount of carbon-14 in their atmospheres would not necessarily be the same as on Earth, she said.
All in all, the results "do not show anything mysterious that could indicate life compounds that do not exist on Earth," Fierro said.