メガロドン: 海洋最大の捕食者 — 絶滅したのか、それとも隠れたのか?
Last updated: 16 Apr 2026
概要
オトドゥス・メガロドンは、これまで地球の海を歩き回った中で最大のサメであるが、 約360万年前に絶滅した。それでも執拗な目撃情報、異常 深海のソナー測定値と海の広大な未踏の深さは憶測を煽り続けています 生き残った人々が深淵に潜むかもしれないということだ。
重要な事実
概要説明
タイムライン
Earliest megalodon ancestors appear in the fossil record.
Accepted extinction date based on the most recent verified fossil evidence.
HMS Challenger expedition dredges megalodon teeth from the Pacific seafloor; manganese dating initially suggests ages of 10,000–15,000 years.
Australian naturalist David Stead documents fishermen’s accounts of an enormous shark “well over 100 feet” in waters off Broughton Island, NSW.
Sporadic reports of abnormally large sharks from South African and Polynesian waters.
Discovery Channel airs “Megalodon: The Monster Shark Lives,” a widely criticized mockumentary that reignites public interest.
Advances in deep-sea autonomous vehicle technology reveal previously unknown ecosystems below 4,000 meters, renewing scientific interest in deep-ocean megafauna.