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Ternyata Jejak Kaki Bisa Ungkap Kecepatan Makhluk Hidup Berjalan Selama bertahun-tahun para peneliti fosil bintang purba mengandalkan formula ukuran panjang kaki untuk menentukan kecepatan berjalan.
Itu berdasarkan rumus yang dibuat oleh Robert McNeil Alexander, Ahli Zoologi dari Inggris, pada tahun 1976. Jejak panjang kaki ternyata bisa mengungkapkan berapa kecepatan berjalan seseorang menjadi lebih akurat.
Penelitian baru yang dilakukan oleh Javier Ruiz dari Complutense University Madrid, menguji 14 mahasiswa untuk berjalan di Pantai Asturias dan mengukur jejak kaki untuk mengetahui berapa kecepatan berjalannya.
"Dengan menggunakan rumus yang dibuat Alexander, dapat diketahui berapa kecepatan rata-rata berjalan para mahasiswa dengan margin eror 10 sampai 15 persen," kata Ruiz, dilansir Science Daily, Sabtu (29/7).
Ia menambahkan, rumus yang dibuat Alexander menghasilkan data yang sangat akurat. "Alexander telah melakukan perkerjaan yang sangat baik dengan menyajikan data statistik dengan dasar ilmu matematika," ujar Ruiz.
Setelah melakukan uji coba dengan para mahasiswa, Ruiz pun melanjutkan penelitian dengan mengukur jejak langkah dari fosil-fosil pada zaman Pleistosen yaitu zaman yang berlangsung pada 1.808.000 hingga 11.500 tahun yang lalu.
"Rumus itu pun bisa memperkirakan berapa kecepatan berjalan dari makhluk yang hidup di Zaman Pleistosen. Bahkan, rumus itu bisa membedakan apakah makhluk itu sedang berjalan atau berlari," kata Ruiz.
Ruiz juga menjelaskan, bukan hanya jejak kaki yang bisa memperkirakan berapa kecepatan seseorang saat berjalan. Banyak variabel yang dapat menentukan berapa kecepatan berjalan.
"Kadang ada dua ukuran jejak kaki yang sama, tapi memiliki kecepatan yang berbeda. Di beberapa orang, pada saat kecepatan tertentu energi di tubuh akan bekerja secara optimal untuk menghasilkan gerakan yang lebih cepat," jelas Ruiz.