Also, for those concerned that Human brains have shrunk over the last thirty thousand years, there is good news: A large-scale study published in March 2024 by researchers at UC Davis Health found human brains have been getting larger over the last few decades. Study participants born in the 1970s had 6.6% larger brain volumes and almost 15% larger brain surface area than those born in the 1930s. This steady increase for people born after the 1930s, is believed to be due to better nutrition. https://health.ucdavis.edu/news/headlines/human-brains-are-getting-larger-that-may-be-good-news-for-dementia-risk/2024/03

These are the massive black holes that lurk at the core of most galaxies. Like the one at the center of our own milkyway galaxy. The question remains do they form at the center of baby galaxies or are they the seed which triggers a galaxy to develop and they just grow even larger over time. If early galaxies had massive black holes for their galaxy size, that suggests the last option. Primordial black holes that is ones that were formed in the big bang have been a possibility for a long time. They have been talked about by astronomers since the 1970s. It great that so much is being discovered now. Lots of surprises still coming I suspect. More info on primeval black holes here. https://physicsworld.com/a/concerning-primordial-black-holes/